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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th21</font></span>: <a NAME="T21"><span class="comment"><font color="firebrick">:: ROBBINS3:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">K</font>, <font color="Olive" title="b2">L</font> being   non  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>   <a href="robbins1.html#L4" title="ROBBINS1:struct.4">OrthoLattStr</a>   st  <a href="robbins1.html#G4" title="ROBBINS1:aggr.4">OrthoLattStr</a>(#  the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Olive" title="b1">K</font>, the <a href="lattices.html#U2" title="LATTICES:sel.2">L_join</a> of <font color="Olive" title="b1">K</font>, the <a href="lattices.html#U1" title="LATTICES:sel.1">L_meet</a> of <font color="Olive" title="b1">K</font>, the <a href="robbins1.html#U1" title="ROBBINS1:sel.1">Compl</a> of <font color="Olive" title="b1">K</font> #) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="robbins1.html#G4" title="ROBBINS1:aggr.4">OrthoLattStr</a>(#  the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Olive" title="b2">L</font>, the <a href="lattices.html#U2" title="LATTICES:sel.2">L_join</a> of <font color="Olive" title="b2">L</font>, the <a href="lattices.html#U1" title="LATTICES:sel.1">L_meet</a> of <font color="Olive" title="b2">L</font>, the <a href="robbins1.html#U1" title="ROBBINS1:sel.1">Compl</a> of <font color="Olive" title="b2">L</font> #) &amp; <font color="Olive" title="b1">K</font> is  <a href="robbins3.html#V8" title="ROBBINS3:attr.8">involutive</a>  holds <br/><font color="Olive" title="b2">L</font> is  <a href="robbins3.html#V8" title="ROBBINS3:attr.8">involutive</a> </div></div>
