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<b>let </b><font color="Maroon">c<sub>1</sub></font> be   <a href="pre_topc.html#NM1">TopSpace</a>;<br/><b>let </b><font color="Maroon">c<sub>2</sub></font> be   <a href="struct_0.html#NM2">Subset</a> of <font color="Maroon">c<sub>1</sub></font>;<br/><b>let </b><font color="Maroon">c<sub>3</sub></font> be    <a href="hidden.html#M1">set</a> ;<br/>





<b>assume </b><a NAME="E1:22"/>
<font color="Maroon">c<sub>3</sub></font> <a href="topgen_1.html#R1" target="_self">is_an_accumulation_point_of</a> <font color="Maroon">c<sub>2</sub></font>
 ;<br/>

<a NAME="E2:22"/><b>then </b>
<font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R2">in</a>  <a href="pre_topc.html#K4">Cl</a> <span class="p1">(<span class="default"><font color="Maroon">c<sub>2</sub></font> <a href="subset_1.html#K7">\</a> <span class="p2"><a href="tarski.html#K1">{</a><span class="default"><font color="Maroon">c<sub>3</sub></font></span><a href="tarski.html#K1">}</a></span></span>)</span>
 
<b>by </b><i><a class="ref" href="topgen_1.html#D2" target="_self">Def2</a></i>;<br/>
<b>hence </b><a NAME="E3:22"/>
<font color="Maroon">c<sub>3</sub></font> is   <a href="pre_topc.html#NM2">Point</a> of <font color="Maroon">c<sub>1</sub></font>
 ;<br/>


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