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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E19">Th11</font></span>: <a NAME="T11"><span class="comment"><font color="firebrick">:: AOFA_I00:11</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font> being   <a href="card_3.html#V4" title="CARD_3:attr.4">countable</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a> <br/>  for <font color="Olive" title="b2">f</font> being   <a href="aofa_i00.html#NM2" title="AOFA_I00:NM.2">Enumeration</a> of <font color="Olive" title="b1">X</font> holds   <a href="relset_1.html#K2" title="RELSET_1:func.2">rng</a> <font color="Olive" title="b2">f</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a> </div></div>
