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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E2">Th4</font></span>: <a NAME="T4"><span class="comment"><font color="firebrick">:: MARGREL1:4</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</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="margrel1.html#M2" title="MARGREL1:mode.2">relation</a> of <font color="Olive" title="b1">X</font></div></div>
