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<b>let </b><font color="Maroon">c<sub>1</sub></font> be   <a href="lattices.html#NM8">B_Lattice</a>;<br/><b>let </b><font color="Maroon">c<sub>2</sub></font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">c<sub>1</sub></font>;<br/><b>let </b><font color="Maroon">c<sub>3</sub></font> be   <a href="struct_0.html#NM1">Element</a> of <span class="p1">(<span class="default"><font color="Maroon">c<sub>1</sub></font> <a href="lattice2.html#K1">.:</a> </span>)</span>;<br/>





<a NAME="E1:80"/>
( <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">c<sub>3</sub></font></span>)</span> <a href="filter_2.html#K5" target="_self">.:</a>  <a href="hidden.html#R1">=</a>  <a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">c<sub>3</sub></font> &amp;  <a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>3</sub></font> )
 
;<br/>
<b>hence </b><a NAME="E2:80"/>
( <span class="p1">(<span class="default"><font color="Maroon">c<sub>2</sub></font> <a href="filter_2.html#K5" target="_self">.:</a> </span>)</span> <a href="lattices.html#K7">`</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> <a href="lattices.html#K7">`</a>  &amp; <span class="p1">(<span class="default"><a href="filter_2.html#K6" target="_self">.:</a> <font color="Maroon">c<sub>3</sub></font></span>)</span> <a href="lattices.html#K7">`</a>  <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>3</sub></font> <a href="lattices.html#K7">`</a>  )
 <b>by </b><i><a class="txt" href="filter_2.html#E70"><i><font color="Green">Lemma30</font></i></a></i>;<br/>


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