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<b>let </b><font color="Maroon" title="c1">A</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>let </b><font color="Maroon" title="c2">p</font>, <font color="Maroon" title="c3">q</font> be   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <span class="p1">(<span class="default"><a href="normform.html#K12" title="NORMFORM:func.12">NormForm</a> <font color="Maroon" title="c1">A</font></span>)</span>; <i><font color="Red">:: according to </font></i><a class="ref" href="filter_0.html#D7" title="FILTER_0:def.7">FILTER_0:def 7</a><br/>



<b>take </b><font color="Maroon" title="c4">r</font> =  <a href="lattice2.html#K2" title="LATTICE2:func.2">FinJoin</a> <span class="p1">(<span class="default"><a href="heyting1.html#K10" title="HEYTING1:func.10">SUB</a> <font color="Maroon" title="c2">p</font></span>)</span>,<span class="p1">(<span class="default"><font color="Maroon">H<sub>2</sub></font>(<font color="Maroon" title="c1">A</font>) <a href="funcop_1.html#K6" title="FUNCOP_1:func.6">.:</a> <span class="p2">(<span class="default"><a href="heyting1.html#K8" title="HEYTING1:func.8">pseudo_compl</a> <font color="Maroon" title="c1">A</font></span>)</span>,<span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="heyting1.html#K9" title="HEYTING1:func.9">StrongImpl</a> <font color="Maroon" title="c1">A</font></span>)</span> <a href="funcop_1.html#K9" title="FUNCOP_1:func.9">[:]</a> <span class="p3">(<span class="default"><a href="heyting1.html#K11" title="HEYTING1:func.11">diff</a> <font color="Maroon" title="c2">p</font></span>)</span>,<font color="Maroon" title="c3">q</font></span>)</span></span>)</span>;<br/>

<b>thus </b><a NAME="E1:44"/>
( <font color="Maroon" title="c2">p</font> <a href="lattices.html#K4" title="LATTICES:func.4">"/\"</a> <font color="Maroon" title="c4">r</font> <a href="lattices.html#R3" title="LATTICES:pred.3">[=</a> <font color="Maroon" title="c3">q</font> &amp; ( for <font color="Olive" title="b1">r1</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <span class="p1">(<span class="default"><a href="normform.html#K12" title="NORMFORM:func.12">NormForm</a> <font color="Maroon" title="c1">A</font></span>)</span>  st <font color="Maroon" title="c2">p</font> <a href="lattices.html#K4" title="LATTICES:func.4">"/\"</a> <font color="Olive" title="b1">r1</font> <a href="lattices.html#R3" title="LATTICES:pred.3">[=</a> <font color="Maroon" title="c3">q</font> holds <br/><font color="Olive" title="b1">r1</font> <a href="lattices.html#R3" title="LATTICES:pred.3">[=</a> <font color="Maroon" title="c4">r</font> ) )
 <b>by </b><i><a class="txt" href="heyting1.html#E51"><i><font color="Green" title="E39">Lm9</font></i></a></i>;<br/>


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