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<div><span class="kw">theorem </span><a NAME="T131"><span class="comment"><font color="firebrick">:: SEQ_4:131</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">A</font> being   <a href="subset_1.html#NM2" title="SUBSET_1:NM.2">Subset</a> of <span class="p1">(<span class="default"><a href="seq_4.html#K12" title="SEQ_4:func.12">COMPLEX</a> <font color="Olive" title="b1">n</font></span>)</span> holds <br/> ( <font color="Olive" title="b2">A</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="seq_4.html#K25" title="SEQ_4:func.25">ComplexOpenSets</a> <font color="Olive" title="b1">n</font> iff <font color="Olive" title="b2">A</font> is  <a href="seq_4.html#V1" title="SEQ_4:attr.1">open</a>  )</div></div>
