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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th20</font></span>: <a NAME="T21"><span class="comment"><font color="firebrick">:: CARDFIL4:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">B</font> being    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="cardfil2.html#K11" title="CARDFIL2:func.11">base_of_frechet_filter</a>   ex <font color="Olive" title="b2">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a> st <font color="Olive" title="b1">B</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a> <a href="subset_1.html#K6" title="SUBSET_1:func.6">\</a> <span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">Segm</a> <font color="Olive" title="b2">n</font></span>)</span></div></div>
