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<b>let </b><font color="Maroon">X</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">y</font> be    <a href="subset_1.html#M1">Element</a> of <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><span class="p2">(<span class="default"><a href="finsub_1.html#K5">Fin</a> <font color="Maroon">X</font></span>)</span>,<span class="p2">(<span class="default"><a href="finsub_1.html#K5">Fin</a> <font color="Maroon">X</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span>;<br/>



<a NAME="E1:31"/>
( <font color="Maroon">y</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">X</font> iff  ex <font color="Olive">a</font> being   <a href="subset_1.html#M1">Element</a> of <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><span class="p2">(<span class="default"><a href="finsub_1.html#K5">Fin</a> <font color="Maroon">X</font></span>)</span>,<span class="p2">(<span class="default"><a href="finsub_1.html#K5">Fin</a> <font color="Maroon">X</font></span>)</span></span><a href="zfmisc_1.html#K2">:]</a></span> st <br/>( <font color="Maroon">y</font> <a href="hidden.html#R1">=</a> <font color="Olive">a</font> &amp; <font color="Olive">a</font> <a href="domain_1.html#K2">`1</a>  <a href="xboole_0.html#R1">misses</a> <font color="Olive">a</font> <a href="domain_1.html#K3">`2</a>  ) )
 
;<br/>
<b>hence </b><a NAME="E2:31"/>
( <font color="Maroon">y</font> <a href="hidden.html#R2">in</a>  <a href="normform.html#K7" target="_self">DISJOINT_PAIRS</a> <font color="Maroon">X</font> iff <font color="Maroon">y</font> <a href="domain_1.html#K2">`1</a>  <a href="xboole_0.html#R1">misses</a> <font color="Maroon">y</font> <a href="domain_1.html#K3">`2</a>  )
 ;<br/>


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