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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E9">ThEx</font></span>: <a NAME="T24"><span class="comment"><font color="firebrick">:: COUNTERS:24</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="counters.html#V2" title="COUNTERS:attr.2">ext-natural-membered</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>   ex <font color="Olive" title="b2">N</font> being   <a href="counters.html#NM1" title="COUNTERS:NM.1">ExtNat</a> st <font color="Olive" title="b2">N</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Olive" title="b1">X</font></div></div>
