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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E19">Th15</font></span>: <a NAME="T15"><span class="comment"><font color="firebrick">:: HEYTING1:15</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">a</font> being    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="normform.html#K7" title="NORMFORM:func.7">DISJOINT_PAIRS</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> holds  <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K4" title="TARSKI:func.4">[</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>,<a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K4" title="TARSKI:func.4">]</a></span></div></div>
