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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E24">Th20</font></span>: <a NAME="T20"><span class="comment"><font color="firebrick">:: SCMYCIEL:20</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">G</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="classes1.html#V1" title="CLASSES1:attr.1">subset-closed</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>  holds   <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Olive" title="b1">G</font></div></div>
