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<b>let </b><font color="Maroon">p'</font> be   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1">.:</a> </span>)</span>; <i><font color="Red">:: according to </font></i><a class="ref" href="lattice4.html#D10">LATTICE4:def 10</a><br/><b>let </b><font color="Maroon">q'</font> be   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">L</font> <a href="lattice2.html#K1">.:</a> </span>)</span>;<br/>



<a NAME="E1:29_1_1"/>
( <font color="Maroon">S</font> <a href="filter_2.html#K7" target="_self">.:</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">S</font> &amp; <font color="Maroon">H<sub>1</sub></font>(<font color="Maroon">L</font> <a href="lattice2.html#K1">.:</a> ) <a href="hidden.html#R1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Maroon">L</font>) &amp;  <a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">p'</font> <a href="hidden.html#R1">=</a> <font color="Maroon">p'</font> &amp;  <a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">q'</font> <a href="hidden.html#R1">=</a> <font color="Maroon">q'</font> &amp; <font color="Maroon">p'</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">q'</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">p'</font></span>)</span> <a href="lattices.html#K4">"/\"</a> <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">q'</font></span>)</span> &amp; <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">p'</font></span>)</span> <a href="lattices.html#K3">"\/"</a> <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">q'</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">p'</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">q'</font> )
 
;<br/>
<b>hence </b><a NAME="E2:29_1_1"/>
(  not <font color="Maroon">p'</font> <a href="hidden.html#R2">in</a> <font color="Maroon">S</font> <a href="filter_2.html#K7" target="_self">.:</a>  or  not <font color="Maroon">q'</font> <a href="hidden.html#R2">in</a> <font color="Maroon">S</font> <a href="filter_2.html#K7" target="_self">.:</a>  or ( <font color="Maroon">p'</font> <a href="lattices.html#K4">"/\"</a> <font color="Maroon">q'</font> <a href="hidden.html#R2">in</a> <font color="Maroon">S</font> <a href="filter_2.html#K7" target="_self">.:</a>  &amp; <font color="Maroon">p'</font> <a href="lattices.html#K3">"\/"</a> <font color="Maroon">q'</font> <a href="hidden.html#R2">in</a> <font color="Maroon">S</font> <a href="filter_2.html#K7" target="_self">.:</a>  ) )
 <b>by </b><i><a class="ref" href="lattice4.html#D10">LATTICE4:def 10</a></i>;<br/>


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