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<span class="kw">let </span><font color="Maroon" title="c2">T1</font>, <font color="Maroon" title="c3">T2</font> be   <a href="triang_1.html#V2" title="TRIANG_1:attr.2">strict</a>   <a href="triang_1.html#V3" title="TRIANG_1:attr.3">lower_non-empty</a>   <a href="triang_1.html#L1" title="TRIANG_1:struct.1">TriangStr</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> (  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K1" title="TARSKI:func.1">{</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K1" title="TARSKI:func.1">}</a></span> &amp; (  for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a>  st <font color="Olive" title="b1">n</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  holds <br/> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b2">A</font>)</span>)</span> where <font color="Olive" title="b2">A</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b2">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">n</font> </span> } </span>  ) &amp; (  for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">f</font> being   <a href="triang_1.html#NM4" title="TRIANG_1:NM.4">Face</a> of <font color="Olive" title="b1">n</font><br/>  for <font color="Olive" title="b3">s</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>  st <font color="Olive" title="b3">s</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> holds <br/> for <font color="Olive" title="b4">A</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font>  st  <a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b3">s</font> holds <br/> <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Olive" title="b3">s</font>,<font color="Olive" title="b2">f</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>)</span>)</span> <a href="funct_1.html#NK3" title="FUNCT_1:NK.3">*</a> <font color="Olive" title="b2">f</font> ) &amp;  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K1" title="TARSKI:func.1">{</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K1" title="TARSKI:func.1">}</a></span> &amp; (  for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a>  st <font color="Olive" title="b1">n</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  holds <br/> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b2">A</font>)</span>)</span> where <font color="Olive" title="b2">A</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b2">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">n</font> </span> } </span>  ) &amp; (  for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">f</font> being   <a href="triang_1.html#NM4" title="TRIANG_1:NM.4">Face</a> of <font color="Olive" title="b1">n</font><br/>  for <font color="Olive" title="b3">s</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>  st <font color="Olive" title="b3">s</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> holds <br/> for <font color="Olive" title="b4">A</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font>  st  <a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b3">s</font> holds <br/> <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Olive" title="b3">s</font>,<font color="Olive" title="b2">f</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>)</span>)</span> <a href="funct_1.html#NK3" title="FUNCT_1:NK.3">*</a> <font color="Olive" title="b2">f</font> ) implies <font color="Maroon" title="c2">T1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">T2</font> )</span><br/>

<span class="kw">assume </span><span class="kw">that </span><br/><a NAME="E1:29_1_2"/><span class="lab"><font color="Green" title="E9">A66</font></span>: 
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K1" title="TARSKI:func.1">{</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K1" title="TARSKI:func.1">}</a></span>
 <span class="kw">and </span><br/><a NAME="E2:29_1_2"/><span class="lab"><font color="Green" title="E10">A67</font></span>: 
 for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a>  st <font color="Olive" title="b1">n</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  holds <br/> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b2">A</font>)</span>)</span> where <font color="Olive" title="b2">A</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b2">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">n</font> </span> } </span> 
 <span class="kw">and </span><br/><a NAME="E3:29_1_2"/><span class="lab"><font color="Green" title="E11">A68</font></span>: 
 for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">f</font> being   <a href="triang_1.html#NM4" title="TRIANG_1:NM.4">Face</a> of <font color="Olive" title="b1">n</font><br/>  for <font color="Olive" title="b3">s</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>  st <font color="Olive" title="b3">s</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> holds <br/> for <font color="Olive" title="b4">A</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font>  st  <a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b3">s</font> holds <br/> <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Olive" title="b3">s</font>,<font color="Olive" title="b2">f</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>)</span>)</span> <a href="funct_1.html#NK3" title="FUNCT_1:NK.3">*</a> <font color="Olive" title="b2">f</font>
 <span class="kw">and </span><br/><a NAME="E4:29_1_2"/><span class="lab"><font color="Green" title="E12">A69</font></span>: 
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K1" title="TARSKI:func.1">{</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K1" title="TARSKI:func.1">}</a></span>
 <span class="kw">and </span><br/><a NAME="E5:29_1_2"/><span class="lab"><font color="Green" title="E13">A70</font></span>: 
 for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a>  st <font color="Olive" title="b1">n</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  holds <br/> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b2">A</font>)</span>)</span> where <font color="Olive" title="b2">A</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b2">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">n</font> </span> } </span> 
 <span class="kw">and </span><br/><a NAME="E6:29_1_2"/><span class="lab"><font color="Green" title="E14">A71</font></span>: 
 for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">f</font> being   <a href="triang_1.html#NM4" title="TRIANG_1:NM.4">Face</a> of <font color="Olive" title="b1">n</font><br/>  for <font color="Olive" title="b3">s</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>  st <font color="Olive" title="b3">s</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> holds <br/> for <font color="Olive" title="b4">A</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font>  st  <a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b3">s</font> holds <br/> <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Olive" title="b3">s</font>,<font color="Olive" title="b2">f</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b4">A</font>)</span>)</span> <a href="funct_1.html#NK3" title="FUNCT_1:NK.3">*</a> <font color="Olive" title="b2">f</font>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c2">T1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">T2</font></span><br/>

<a NAME="E7:29_1_2"/><span class="lab"><font color="Green" title="E15">A72</font></span>: 
 for <font color="Olive" title="b1">x</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>   st <font color="Olive" title="b1">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  holds <br/> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">x</font>
 
<div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="29_1_2_1"><span class="kw">proof </span></a><div class="add">

<span class="kw">let </span><font color="Maroon" title="c4">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  implies  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font> )</span><br/>

<span class="kw">assume </span><a NAME="E1:29_1_2_1"/>
<font color="Maroon" title="c4">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font></span><br/>

<span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c5">n</font> = <font color="Maroon" title="c4">x</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  ;<br/>
<div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="29_1_2_1_1"><span class="kw">now </span> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span></a><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="29_1_2_1_1_1"><span class="kw">per </span></a><a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="kw">cases </span></a><span class="hide"><a NAME="E1:29_1_2_1_1_1"/>
( <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  or <font color="Maroon" title="c5">n</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  )
 </span>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="29_1_2_1_1_1_1"><span class="kw">suppose </span></a><a NAME="E1:29_1_2_1_1_1_1"/>
<font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span><br/><div class="add"><span class="kw">hence </span><a NAME="E2:29_1_2_1_1_1_1"/>
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:29_1_2"><span class="lab"><font color="Green" title="E9">A66</font></span></a>, <a class="txt" href="#E4:29_1_2"><span class="lab"><font color="Green" title="E12">A69</font></span></a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="29_1_2_1_1_1_2"><span class="kw">suppose </span></a><a NAME="E1:29_1_2_1_1_1_2"/><span class="lab"><font color="Green" title="E16">A73</font></span>: 
<font color="Maroon" title="c5">n</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span><br/><div class="add"><a NAME="E2:29_1_2_1_1_1_2"/><span class="kw">then </span>
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b1">s</font>)</span>)</span> where <font color="Olive" title="b1">s</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b1">s</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">n</font> </span> } </span> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:29_1_2"><span class="lab"><font color="Green" title="E10">A67</font></span></a></span>;<br/><span class="kw">hence </span><a NAME="E3:29_1_2_1_1_1_2"/>
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E5:29_1_2"><span class="lab"><font color="Green" title="E13">A70</font></span></a>, <a class="txt" href="#E1:29_1_2_1_1_1_2"><span class="lab"><font color="Green" title="E16">A73</font></span></a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div></div><span class="kw">end;</span></div></div><span class="kw">end;</span></div>
<span class="kw">hence </span><a NAME="E4:29_1_2_1"/>
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">x</font>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>
<a NAME="E8:29_1_2"/><span class="kw">then </span><span class="lab"><font color="Green" title="E16">A74</font></span>: 
 the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="pboole.html#R8" title="PBOOLE:pred.8">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c3">T2</font>
 
;<br/>
<div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="29_1_2_2"><span class="kw">now </span> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">i</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>   st <font color="Olive" title="b1">i</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  holds <br/> the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">i</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">i</font></span></a><div class="add"><span class="kw">let </span><font color="Maroon" title="c4">i</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c4">i</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  implies  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font> )</span><br/><span class="kw">assume </span><a NAME="E1:29_1_2_2"/>
<font color="Maroon" title="c4">i</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font></span><br/><span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c5">n</font> = <font color="Maroon" title="c4">i</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>  ;<br/><span class="kw">reconsider </span><font color="Maroon" title="c6">F1n</font> =  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>, <font color="Maroon" title="c7">F2n</font> =  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <span class="p1">(<span class="default"><a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span>)</span>,<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="triang_1.html#K2" title="TRIANG_1:func.2">FuncsSeq</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span>)</span> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E8:29_1_2"><span class="lab"><font color="Green" title="E16">A74</font></span></a>, <a class="ref" href="pboole.html#D15" onmouseover="rs('pboole/D15')" onmouseout="rh()">PBOOLE:def 15</a></span>;<br/><a NAME="E4:29_1_2_2"/><span class="lab"><font color="Green" title="E17">A75</font></span>: 
 <a href="relat_1.html#NK1" title="RELAT_1:NK.1">dom</a> <font color="Maroon" title="c7">F2n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="funct_2.html#D1" onmouseover="rs('funct_2/D1')" onmouseout="rh()">FUNCT_2:def 1</a></span>;<br/><div><span class="lab"><font color="Green" title="E18">A76</font></span>: <a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="29_1_2_2_1"><span class="kw">now </span> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">x</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>   st <font color="Olive" title="b1">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> holds <br/><font color="Maroon" title="c6">F1n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">F2n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">x</font></span></a><div class="add"><span class="kw">let </span><font color="Maroon" title="c8">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c8">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font> implies <font color="Maroon" title="c6">F1n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">F2n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font> )</span><br/><span class="kw">assume </span><a NAME="E1:29_1_2_2_1"/>
<font color="Maroon" title="c8">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c6">F1n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">F2n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font></span><br/><span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c9">x1</font> = <font color="Maroon" title="c8">x</font> as   <a href="triang_1.html#NM4" title="TRIANG_1:NM.4">Face</a> of <font color="Maroon" title="c5">n</font> ;<br/><a NAME="E3:29_1_2_2_1"/>
<font color="Maroon" title="c6">F1n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <span class="p1">(<span class="default"><a href="triang_1.html#K2" title="TRIANG_1:func.2">FuncsSeq</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 ;<br/><a NAME="E4:29_1_2_2_1"/><span class="kw">then </span>
<font color="Maroon" title="c6">F1n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="funct_2.html#K1" title="FUNCT_2:func.1">Funcs</a> (<span class="p1">(<span class="default"> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p2">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span></span>)</span>,<span class="p1">(<span class="default"> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span>)</span>)
 <span class="kw">by</span> <span class="lab"><a class="ref" href="triang_1.html#D3" target="_self" onmouseover="rs('triang_1/D3')" onmouseout="rh()">Def3</a></span>;<br/><span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c10">F1nx</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><span class="kw"> such that </span><br/><a NAME="E6:29_1_2_2_1"/><span class="lab"><font color="Green" title="E19">A77</font></span>: 
<font color="Maroon" title="c10">F1nx</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c6">F1n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font>
 <span class="kw">and </span><br/><a NAME="E7:29_1_2_2_1"/><span class="lab"><font color="Green" title="E20">A78</font></span>: 
 <a href="relat_1.html#NK1" title="RELAT_1:NK.1">dom</a> <font color="Maroon" title="c10">F1nx</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>
 <span class="kw">and </span><br/><a NAME="E8:29_1_2_2_1"/>
 <a href="xtuple_0.html#K10" title="XTUPLE_0:func.10">rng</a> <font color="Maroon" title="c10">F1nx</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="funct_2.html#D2" onmouseover="rs('funct_2/D2')" onmouseout="rh()">FUNCT_2:def 2</a></span>;<br/><a NAME="E9:29_1_2_2_1"/>
<font color="Maroon" title="c7">F2n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <span class="p1">(<span class="default"><a href="triang_1.html#K2" title="TRIANG_1:func.2">FuncsSeq</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 ;<br/><a NAME="E10:29_1_2_2_1"/><span class="kw">then </span>
<font color="Maroon" title="c7">F2n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="funct_2.html#K1" title="FUNCT_2:func.1">Funcs</a> (<span class="p1">(<span class="default"> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p2">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span></span>)</span>,<span class="p1">(<span class="default"> the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font></span>)</span>)
 <span class="kw">by</span> <span class="lab"><a class="ref" href="triang_1.html#D3" target="_self" onmouseover="rs('triang_1/D3')" onmouseout="rh()">Def3</a></span>;<br/><span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c11">F2nx</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><span class="kw"> such that </span><br/><a NAME="E12:29_1_2_2_1"/><span class="lab"><font color="Green" title="E21">A79</font></span>: 
<font color="Maroon" title="c11">F2nx</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">F2n</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c9">x1</font>
 <span class="kw">and </span><br/><a NAME="E13:29_1_2_2_1"/><span class="lab"><font color="Green" title="E22">A80</font></span>: 
 <a href="relat_1.html#NK1" title="RELAT_1:NK.1">dom</a> <font color="Maroon" title="c11">F2nx</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>
 <span class="kw">and </span><br/><a NAME="E14:29_1_2_2_1"/>
 <a href="xtuple_0.html#K10" title="XTUPLE_0:func.10">rng</a> <font color="Maroon" title="c11">F2nx</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="funct_2.html#D2" onmouseover="rs('funct_2/D2')" onmouseout="rh()">FUNCT_2:def 2</a></span>;<br/><div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="29_1_2_2_1_1"><span class="kw">now </span> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">y</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>   st <font color="Olive" title="b1">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> holds <br/><font color="Maroon" title="c10">F1nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c11">F2nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">y</font></span></a><div class="add"><span class="kw">let </span><font color="Maroon" title="c12">y</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c12">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> implies <font color="Maroon" title="c10">F1nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c11">F2nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font> )</span><br/><span class="kw">assume </span><a NAME="E1:29_1_2_2_1_1"/><span class="lab"><font color="Green" title="E23">A81</font></span>: 
<font color="Maroon" title="c12">y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  the <a href="triang_1.html#U1" title="TRIANG_1:sel.1">SkeletonSeq</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c10">F1nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c11">F2nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font></span><br/><span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c13">y1</font> = <font color="Maroon" title="c12">y</font> as   <a href="triang_1.html#NM3" title="TRIANG_1:NM.3">Symplex</a> of <font color="Maroon" title="c2">T1</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> ;<br/><a NAME="E3:29_1_2_2_1_1"/><span class="lab"><font color="Green" title="E24">A82</font></span>: 
<font color="Maroon" title="c10">F1nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c13">y1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Maroon" title="c13">y1</font>,<font color="Maroon" title="c9">x1</font>)
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E6:29_1_2_2_1"><span class="lab"><font color="Green" title="E19">A77</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a>, <a class="ref" href="triang_1.html#D7" target="_self" onmouseover="rs('triang_1/D7')" onmouseout="rh()">Def7</a></span>;<br/><span class="kw">reconsider </span><font color="Maroon" title="c14">y2</font> = <font color="Maroon" title="c12">y</font> as   <a href="triang_1.html#NM3" title="TRIANG_1:NM.3">Symplex</a> of <font color="Maroon" title="c3">T2</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E7:29_1_2"><span class="lab"><font color="Green" title="E15">A72</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a></span>;<br/><a NAME="E5:29_1_2_2_1_1"/><span class="lab"><font color="Green" title="E25">A83</font></span>: 
<font color="Maroon" title="c11">F2nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c14">y2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Maroon" title="c14">y2</font>,<font color="Maroon" title="c9">x1</font>)
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E8:29_1_2"><span class="lab"><font color="Green" title="E16">A74</font></span></a>, <a class="txt" href="#E12:29_1_2_2_1"><span class="lab"><font color="Green" title="E21">A79</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a>, <a class="ref" href="triang_1.html#D7" target="_self" onmouseover="rs('triang_1/D7')" onmouseout="rh()">Def7</a></span>;<br/><a NAME="E6:29_1_2_2_1_1"/>
<font color="Maroon" title="c13">y1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <span class="p1"> { <span class="default"> <span class="p2">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Olive" title="b1">s</font>)</span>)</span> where <font color="Olive" title="b1">s</font> is   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font> :  <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Olive" title="b1">s</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1 </span> } </span> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:29_1_2"><span class="lab"><font color="Green" title="E10">A67</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a></span>;<br/><span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c15">A</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="pre_poly.html#M1" title="PRE_POLY:mode.1">Element</a> of  <a href="triang_1.html#K1" title="TRIANG_1:func.1">symplexes</a> <font color="Maroon" title="c1">C</font><span class="kw"> such that </span><br/><a NAME="E8:29_1_2_2_1_1"/><span class="lab"><font color="Green" title="E26">A84</font></span>: 
 <a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Maroon" title="c15">A</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c13">y1</font>
 <span class="kw">and </span><br/><a NAME="E9:29_1_2_2_1_1"/>
 <a href="card_1.html#K4" title="CARD_1:func.4">card</a> <font color="Maroon" title="c15">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">n</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1
 ;<br/><a NAME="E10:29_1_2_2_1_1"/>
 <a href="triang_1.html#K5" title="TRIANG_1:func.5">face</a> (<font color="Maroon" title="c13">y1</font>,<font color="Maroon" title="c9">x1</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K7" title="PRE_POLY:func.7">SgmX</a> ( the <a href="orders_2.html#U1" title="ORDERS_2:sel.1">InternalRel</a> of <font color="Maroon" title="c1">C</font>,<font color="Maroon" title="c15">A</font>)</span>)</span> <a href="funct_1.html#NK3" title="FUNCT_1:NK.3">*</a> <font color="Maroon" title="c9">x1</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:29_1_2"><span class="lab"><font color="Green" title="E11">A68</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a>, <a class="txt" href="#E8:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E26">A84</font></span></a></span>;<br/><span class="kw">hence </span><a NAME="E11:29_1_2_2_1_1"/>
<font color="Maroon" title="c10">F1nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c11">F2nx</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c12">y</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E6:29_1_2"><span class="lab"><font color="Green" title="E14">A71</font></span></a>, <a class="txt" href="#E8:29_1_2"><span class="lab"><font color="Green" title="E16">A74</font></span></a>, <a class="txt" href="#E1:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E23">A81</font></span></a>, <a class="txt" href="#E3:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E24">A82</font></span></a>, <a class="txt" href="#E5:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E25">A83</font></span></a>, <a class="txt" href="#E8:29_1_2_2_1_1"><span class="lab"><font color="Green" title="E26">A84</font></span></a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div><span class="kw">hence </span><a NAME="E16:29_1_2_2_1"/>
<font color="Maroon" title="c6">F1n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">F2n</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">x</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E6:29_1_2_2_1"><span class="lab"><font color="Green" title="E19">A77</font></span></a>, <a class="txt" href="#E7:29_1_2_2_1"><span class="lab"><font color="Green" title="E20">A78</font></span></a>, <a class="txt" href="#E12:29_1_2_2_1"><span class="lab"><font color="Green" title="E21">A79</font></span></a>, <a class="txt" href="#E13:29_1_2_2_1"><span class="lab"><font color="Green" title="E22">A80</font></span></a>, <a class="ref" href="funct_1.html#T2" onmouseover="rs('funct_1/T2')" onmouseout="rh()">FUNCT_1:2</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div><a NAME="E6:29_1_2_2"/>
 <a href="relat_1.html#NK1" title="RELAT_1:NK.1">dom</a> <font color="Maroon" title="c6">F1n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <a href="triang_1.html#K4" title="TRIANG_1:func.4">NatEmbSeq</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c5">n</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="funct_2.html#D1" onmouseover="rs('funct_2/D1')" onmouseout="rh()">FUNCT_2:def 1</a></span>;<br/><span class="kw">hence </span><a NAME="E7:29_1_2_2"/>
 the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c2">T1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  the <a href="triang_1.html#U2" title="TRIANG_1:sel.2">FacesAssign</a> of <font color="Maroon" title="c3">T2</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c4">i</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:29_1_2_2"><span class="lab"><font color="Green" title="E17">A75</font></span></a>, <a class="txt" href="#E5:29_1_2_2"><span class="lab"><font color="Green" title="E18">A76</font></span></a>, <a class="ref" href="funct_1.html#T2" onmouseover="rs('funct_1/T2')" onmouseout="rh()">FUNCT_1:2</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div>
<span class="kw">hence </span><a NAME="E10:29_1_2"/>
<font color="Maroon" title="c2">T1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">T2</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E8:29_1_2"><span class="lab"><font color="Green" title="E16">A74</font></span></a>, <a class="ref" href="pboole.html#T3" onmouseover="rs('pboole/T3')" onmouseout="rh()">PBOOLE:3</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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