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<b>set </b><font color="Maroon">X</font> = <span class="p1">(<span class="default"><a href="substut1.html#K10" target="_self">Dom_Bound_Vars</a> <font color="Maroon">p</font></span>)</span> <a href="subset_1.html#K4">\/</a> <span class="p1">(<span class="default"><a href="substut1.html#K11" target="_self">Sub_Var</a> <font color="Maroon">finSub</font></span>)</span>;<br/>
<a NAME="E1:19_1_1"/>
 <a href="card_1.html#K1">Card</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="substut1.html#K10" target="_self">Dom_Bound_Vars</a> <font color="Maroon">p</font></span>)</span> <a href="subset_1.html#K4">\/</a> <span class="p2">(<span class="default"><a href="substut1.html#K11" target="_self">Sub_Var</a> <font color="Maroon">finSub</font></span>)</span></span>)</span> <a href="hidden.html#R2">in</a>  <a href="card_1.html#K1">Card</a> <a href="numbers.html#K5">NAT</a> 
 
<b>by </b><i><a class="ref" href="card_3.html#T58">CARD_3:58</a></i>;<br/>
<b>hence </b><a NAME="E2:19_1_1"/>
<a href="numbers.html#K5">NAT</a>  <a href="subset_1.html#K7">\</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="substut1.html#K10" target="_self">Dom_Bound_Vars</a> <font color="Maroon">p</font></span>)</span> <a href="subset_1.html#K4">\/</a> <span class="p2">(<span class="default"><a href="substut1.html#K11" target="_self">Sub_Var</a> <font color="Maroon">finSub</font></span>)</span></span>)</span> is  non <a href="xboole_0.html#V1">empty</a> <a href="subset_1.html#NM2">Subset</a> of <a href="numbers.html#K5">NAT</a> 
 <b>by </b><i><a class="ref" href="card_2.html#T4">CARD_2:4</a>, <a class="ref" href="xboole_1.html#T36">XBOOLE_1:36</a></i>;<br/>


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