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<b>reconsider </b><font color="Maroon">c<sub>1</sub></font> = <span class="p1">(<span class="default"><a href="topgen_5.html#K2" target="_self">y&gt;=0-plane</a>  <a href="subset_1.html#K7">\</a> <a href="topgen_5.html#K1" target="_self">y=0-line</a> </span>)</span> <a href="subset_1.html#K8">/\</a> <span class="p1">(<span class="default"><a href="card_3.html#K4">product</a> <span class="p2"><a href="finseq_1.html#K10">&lt;*</a><span class="default"><a href="numbers.html#K3">RAT</a> ,<a href="numbers.html#K3">RAT</a> </span><a href="finseq_1.html#K10">*&gt;</a></span></span>)</span> as  <a href="tops_1.html#V1">dense</a> <a href="struct_0.html#NM2">Subset</a> of <a href="topgen_5.html#K3" target="_self">Niemytzki-plane</a>  <b>by </b><i><a class="ref" href="topgen_5.html#T40" target="_self">Th40</a></i>;<br/>
<a NAME="E2:56"/>
<font color="Maroon">c<sub>1</sub></font> <a href="tarski.html#R1">c=</a>  <a href="card_3.html#K4">product</a> <span class="p1"><a href="finseq_1.html#K10">&lt;*</a><span class="default"><a href="numbers.html#K3">RAT</a> ,<a href="numbers.html#K3">RAT</a> </span><a href="finseq_1.html#K10">*&gt;</a></span>
 
<b>by </b><i><a class="ref" href="xboole_1.html#T17">XBOOLE_1:17</a></i>;<br/>
<a NAME="E3:56"/><b>then </b>
(  <a href="topgen_1.html#K4">density</a> <a href="topgen_5.html#K3" target="_self">Niemytzki-plane</a>  <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_1.html#K1">Card</a> <font color="Maroon">c<sub>1</sub></font> &amp;  <a href="card_1.html#K1">Card</a> <font color="Maroon">c<sub>1</sub></font> <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_1.html#K1">Card</a> <span class="p1">(<span class="default"><a href="card_3.html#K4">product</a> <span class="p2"><a href="finseq_1.html#K10">&lt;*</a><span class="default"><a href="numbers.html#K3">RAT</a> ,<a href="numbers.html#K3">RAT</a> </span><a href="finseq_1.html#K10">*&gt;</a></span></span>)</span> )
 
<b>by </b><i><a class="ref" href="card_1.html#T27">CARD_1:27</a>, <a class="ref" href="topgen_1.html#D12">TOPGEN_1:def 12</a></i>;<br/>
<a NAME="E4:56"/><b>then </b>
 <a href="topgen_1.html#K4">density</a> <a href="topgen_5.html#K3" target="_self">Niemytzki-plane</a>  <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_1.html#K1">Card</a> <span class="p1">(<span class="default"><a href="card_3.html#K4">product</a> <span class="p2"><a href="finseq_1.html#K10">&lt;*</a><span class="default"><a href="numbers.html#K3">RAT</a> ,<a href="numbers.html#K3">RAT</a> </span><a href="finseq_1.html#K10">*&gt;</a></span></span>)</span>
 
<b>by </b><i><a class="ref" href="xboole_1.html#T1">XBOOLE_1:1</a></i>;<br/>
<b>hence </b><a NAME="E5:56"/>
 <a href="topgen_1.html#K4">density</a> <a href="topgen_5.html#K3" target="_self">Niemytzki-plane</a>  <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_1.html#K3">alef</a> 0
 <b>by </b><i><a class="ref" href="card_4.html#T54">CARD_4:54</a>, <a class="ref" href="topgen_3.html#T17">TOPGEN_3:17</a>, <a class="ref" href="topgen_5.html#T12" target="_self">Th12</a></i>; <i><font color="Red">:: according to </font></i><a class="ref" href="topgen_1.html#D13">TOPGEN_1:def 13</a><br/>


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