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<span class="kw">set </span><font color="Maroon" title="c3">MF</font> = <font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p1">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span>;<br/>
<a NAME="E1:47_1_1"/>
<font color="Maroon" title="c1">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> 
 
;<br/>
<span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c4">n1</font> = <font color="Maroon" title="c1">n</font> <a href="xxreal_3.html#K3" title="XXREAL_3:func.3">-</a> 1 as   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a> <span class="kw">by</span> <span class="lab"><a class="ref" href="nat_1.html#T20" onmouseover="rs('nat_1/T20')" onmouseout="rh()">NAT_1:20</a></span>;<br/>
<a NAME="E3:47_1_1"/><span class="lab"><font color="Green" title="E19">A1</font></span>: 
 <a href="struct_0.html#K2" title="STRUCT_0:func.2">[#]</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font>
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="pre_topc.html#D5" onmouseover="rs('pre_topc/D5')" onmouseout="rh()">PRE_TOPC:def 5</a></span>;<br/>
<div><span class="lab"><font color="Green" title="E20">A2</font></span>: <a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="47_1_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">pF</font> being   <a href="pre_topc.html#NM2" title="PRE_TOPC:NM.2">Point</a> of <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span>  ex <font color="Olive" title="b2">W</font> being    <a href="connsp_2.html#M1" title="CONNSP_2:mode.1">a_neighborhood</a> of <font color="Olive" title="b1">pF</font> st <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <font color="Olive" title="b2">W</font>, <a href="mfold_0.html#K1" title="MFOLD_0:func.1">Tball</a> (<span class="p1">(<span class="default"><a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> <font color="Maroon" title="c4">n1</font></span>)</span></span>)</span>,1) <a href="borsuk_3.html#R2" title="BORSUK_3:pred.2">are_homeomorphic</a> </span></a><div class="add"><span class="kw">let </span><font color="Maroon" title="c5">pF</font> be   <a href="pre_topc.html#NM2" title="PRE_TOPC:NM.2">Point</a> of <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></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">  ex <font color="Olive" title="b1">W</font> being    <a href="connsp_2.html#M1" title="CONNSP_2:mode.1">a_neighborhood</a> of <font color="Maroon" title="c5">pF</font> st <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <font color="Olive" title="b1">W</font>, <a href="mfold_0.html#K1" title="MFOLD_0:func.1">Tball</a> (<span class="p1">(<span class="default"><a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> <font color="Maroon" title="c4">n1</font></span>)</span></span>)</span>,1) <a href="borsuk_3.html#R2" title="BORSUK_3:pred.2">are_homeomorphic</a> </span><br/><a NAME="E1:47_1_1_1"/>
<font color="Maroon" title="c5">pF</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="struct_0.html#K2" title="STRUCT_0:func.2">[#]</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span>
 ;<br/><span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c6">p</font> = <font color="Maroon" title="c5">pF</font> as   <a href="pre_topc.html#NM2" title="PRE_TOPC:NM.2">Point</a> of <font color="Maroon" title="c2">M</font> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:47_1_1"><span class="lab"><font color="Green" title="E19">A1</font></span></a></span>;<br/><span class="kw">consider </span><font color="Maroon" title="c7">U</font> being    <a href="connsp_2.html#M1" title="CONNSP_2:mode.1">a_neighborhood</a> of <font color="Maroon" title="c6">p</font><span class="kw"> such that </span><br/><a NAME="E4:47_1_1_1"/><span class="lab"><font color="Green" title="E21">A3</font></span>: 
<font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <font color="Maroon" title="c7">U</font>, <a href="brouwer.html#K2" title="BROUWER:func.2">Tdisk</a> (<span class="p1">(<span class="default"><a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> <font color="Maroon" title="c1">n</font></span>)</span></span>)</span>,1) <a href="borsuk_3.html#R2" title="BORSUK_3:pred.2">are_homeomorphic</a> 
 <span class="kw">by</span> <span class="lab"><a class="ref" href="mfold_0.html#D3" target="_self" onmouseover="rs('mfold_0/D3')" onmouseout="rh()">Def3</a></span>;<br/><a NAME="E5:47_1_1_1"/>
<font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <font color="Maroon" title="c7">U</font>, <a href="brouwer.html#K2" title="BROUWER:func.2">Tdisk</a> (<span class="p1">(<span class="default"><a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> <span class="p3">(<span class="default"><font color="Maroon" title="c4">n1</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1</span>)</span></span>)</span></span>)</span>,1) <a href="borsuk_3.html#R2" title="BORSUK_3:pred.2">are_homeomorphic</a> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:47_1_1_1"><span class="lab"><font color="Green" title="E21">A3</font></span></a></span>;<br/><span class="kw">hence </span><a NAME="E6:47_1_1_1"/>
 ex <font color="Olive" title="b1">W</font> being    <a href="connsp_2.html#M1" title="CONNSP_2:mode.1">a_neighborhood</a> of <font color="Maroon" title="c5">pF</font> st <span class="p1">(<span class="default"><font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p2">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span></span>)</span> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <font color="Olive" title="b1">W</font>, <a href="mfold_0.html#K1" title="MFOLD_0:func.1">Tball</a> (<span class="p1">(<span class="default"><a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <span class="p2">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> <font color="Maroon" title="c4">n1</font></span>)</span></span>)</span>,1) <a href="borsuk_3.html#R2" title="BORSUK_3:pred.2">are_homeomorphic</a> 
 <span class="kw">by</span> <span class="lab"><a class="ref" href="mfold_0.html#T7" target="_self" onmouseover="rs('mfold_0/T7')" onmouseout="rh()">Th7</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="E5:47_1_1"/>
<font color="Maroon" title="c1">n</font> <a href="nat_d.html#K7" title="NAT_D:func.7">-'</a> 1 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">n1</font>
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="xreal_0.html#D2" onmouseover="rs('xreal_0/D2')" onmouseout="rh()">XREAL_0:def 2</a></span>;<br/>
<span class="kw">hence </span><a NAME="E6:47_1_1"/>
 for <font color="Olive">b<sub>1</sub></font> being   non  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>  <a href="pre_topc.html#NM1" title="PRE_TOPC:NM.1">TopSpace</a>  st <font color="Olive">b<sub>1</sub></font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">M</font> <a href="pre_topc.html#K1" title="PRE_TOPC:func.1">|</a> <span class="p1">(<span class="default"><a href="mfold_0.html#K5" title="MFOLD_0:func.5">Fr</a> <font color="Maroon" title="c2">M</font></span>)</span> holds <br/><font color="Olive">b<sub>1</sub></font> is <font color="Maroon" title="c1">n</font> <a href="nat_d.html#K7" title="NAT_D:func.7">-'</a> 1 <a href="mfold_0.html#V2" title="MFOLD_0:attr.2">-locally_euclidean</a> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:47_1_1"><span class="lab"><font color="Green" title="E20">A2</font></span></a>, <a class="ref" href="mfold_0.html#T13" target="_self" onmouseover="rs('mfold_0/T13')" onmouseout="rh()">Th13</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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