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<a NAME="E1:31_2_1"/>
( 0 <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">a</font> &amp; <font color="Maroon">a</font> <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">a</font> &amp; 1 <a href="card_1.html#NR2" target="_self">&lt;`</a> <font color="Maroon">b</font> )
 
<b>by </b><i>, </i>;<br/>
<a NAME="E2:31_2_1"/><b>then </b>
(  <a href="card_2.html#K3">exp</a> <font color="Maroon">a</font>,1 <a href="hidden.html#R1">=</a> <font color="Maroon">a</font> &amp;  <a href="card_2.html#K3">exp</a> <font color="Maroon">a</font>,1 <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_2.html#K3">exp</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> &amp;  <a href="card_1.html#K3">alef</a> 0 <a href="card_1.html#NR1" target="_self">&lt;=`</a> <font color="Maroon">a</font> )
 
<b>by </b><i>, <a class="ref" href="card_2.html#T40">CARD_2:40</a>, <a class="ref" href="card_4.html#T70">CARD_4:70</a></i>;<br/>
<a NAME="E3:31_2_1"/><b>then </b>
 <a href="card_1.html#K3">alef</a> 0 <a href="card_1.html#NR1" target="_self">&lt;=`</a>  <a href="card_2.html#K3">exp</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>
 
<b>by </b><i><a class="ref" href="xboole_1.html#T1">XBOOLE_1:1</a></i>;<br/>
<b>hence </b><a NAME="E4:31_2_1"/>
not  <a href="card_2.html#K3">exp</a> <font color="Maroon">a</font>,<font color="Maroon">b</font> is <a href="finset_1.html#V1">finite</a>
 <b>by </b><i><a class="ref" href="card_4.html#T11">CARD_4:11</a></i>;<br/>


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