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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E16">Th18</font></span>: <a NAME="T18"><span class="comment"><font color="firebrick">:: TOPGEN_4:18</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">T</font> being    <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>  holds   <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  is   <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  <a href="setfam_1.html#NM1" title="SETFAM_1:NM.1">Subset-Family</a> of <font color="Olive" title="b1">T</font></div></div>
