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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E35">Th51</font></span>: <a NAME="T51"><span class="comment"><font color="firebrick">:: CLASSES2:51</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">U</font> being   <a href="classes2.html#NM1" title="CLASSES2:NM.1">Universe</a> holds <br/> (  <a href="ordinal1.html#K2" title="ORDINAL1:func.2">On</a> <font color="Olive" title="b1">U</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  &amp;  <a href="ordinal1.html#K2" title="ORDINAL1:func.2">On</a> <font color="Olive" title="b1">U</font> is  <a href="ordinal1.html#V4" title="ORDINAL1:attr.4">limit_ordinal</a>  )</div></div>
