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<div class="add">

<b>take </b>
 <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a> 
; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> (  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V9" title="SHEFFER1:attr.9">properly_defined</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V7" title="ROBBINS1:attr.7">well-complemented</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="lattices.html#V10" title="LATTICES:attr.10">Lattice-like</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V10" title="SHEFFER1:attr.10">satisfying_Sheffer_1</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V11" title="SHEFFER1:attr.11">satisfying_Sheffer_2</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V12" title="SHEFFER1:attr.12">satisfying_Sheffer_3</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer2.html#V1" title="SHEFFER2:attr.1">satisfying_Sh_1</a> )</span><br/>

<a NAME="E1:73_1_1"/>
 <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a>
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="73_1_1_1"><b>proof </b></a><div class="add">

<a NAME="E1:73_1_1_1"/>
for <font color="Olive" title="b1">x</font>, <font color="Olive" title="b2">y</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  holds  <font color="Olive" title="b1">x</font> <a href="lattices.html#K4" title="LATTICES:func.4">"/\"</a> <font color="Olive" title="b2">y</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Olive" title="b1">x</font> <a href="robbins1.html#K3" title="ROBBINS1:func.3">`</a> </span>)</span> <a href="lattices.html#K3" title="LATTICES:func.3">"\/"</a> <span class="p2">(<span class="default"><font color="Olive" title="b2">y</font> <a href="robbins1.html#K3" title="ROBBINS1:func.3">`</a> </span>)</span></span>)</span> <a href="robbins1.html#K3" title="ROBBINS1:func.3">`</a> 
 
<b>by </b><i><a class="ref" href="struct_0.html#D10" title="STRUCT_0:def.10">STRUCT_0:def 10</a></i>;<br/>
<b>hence </b><a NAME="E2:73_1_1_1"/>
 <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a>
 <b>by </b><i><a class="ref" href="robbins1.html#D23" title="ROBBINS1:def.23">ROBBINS1:def 23</a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


</div><b>end;</b></div>
<b>hence </b><a NAME="E2:73_1_1"/>
(  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V9" title="SHEFFER1:attr.9">properly_defined</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V7" title="ROBBINS1:attr.7">well-complemented</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="lattices.html#V10" title="LATTICES:attr.10">Lattice-like</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V10" title="SHEFFER1:attr.10">satisfying_Sheffer_1</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V11" title="SHEFFER1:attr.11">satisfying_Sheffer_2</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer1.html#V12" title="SHEFFER1:attr.12">satisfying_Sheffer_3</a> &amp;  <a href="sheffer1.html#K4" title="SHEFFER1:func.4">TrivShefferOrthoLattStr</a>  is <a href="sheffer2.html#V1" title="SHEFFER2:attr.1">satisfying_Sh_1</a> )
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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