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<a NAME="E1:72_1_1"/>
( <font color="Maroon">c<sub>2</sub></font> is <a href="pre_topc.html#V3">open</a> &amp; <font color="Maroon">c<sub>2</sub></font> is <a href="pre_topc.html#V4">closed</a> )
 
<b>by </b><i><a class="ref" href="tdlat_3.html#T18">TDLAT_3:18</a>, <a class="ref" href="tdlat_3.html#T17">TDLAT_3:17</a></i>;<br/>
<b>hence </b><a NAME="E2:72_1_1"/>
 <a href="tops_1.html#K2">Fr</a> <font color="Maroon">c<sub>2</sub></font> is <a href="xboole_0.html#V1">empty</a>
 <b>by </b><i><a class="ref" href="topgen_1.html#T16" target="_self">Th16</a></i>;<br/>


</div>
