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<div><span class="kw">theorem </span><a NAME="T40"><span class="comment"><font color="firebrick">:: CARDFIL4:40</font></span><br/></a><div class="add"><span class="p1"><a href="cardfil4.html#K1" title="CARDFIL4:func.1">[:</a><span class="default"><a href="cardfil2.html#K11" title="CARDFIL2:func.11">base_of_frechet_filter</a>,<a href="cardfil2.html#K11" title="CARDFIL2:func.11">base_of_frechet_filter</a></span><a href="cardfil4.html#K1" title="CARDFIL4:func.1">:]</a></span> is   <a href="cardfil2.html#NM2" title="CARDFIL2:NM.2">filter_base</a> of <span class="p1"><a href="zfmisc_1.html#K2" title="ZFMISC_1:func.2">[:</a><span class="default"><a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>,<a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a></span><a href="zfmisc_1.html#K2" title="ZFMISC_1:func.2">:]</a></span> ;<br/></div></div>
