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<b>let </b><font color="Maroon">I</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">X</font> be    <a href="pboole.html#M1" target="_self">ManySortedSet</a> of <font color="Maroon">I</font>;<br/><b>let </b><font color="Maroon">Y</font> be    <a href="pboole.html#M1" target="_self">ManySortedSet</a> of <font color="Maroon">I</font>;<br/>





<div><b>hereby </b>
<div class="add"><b>assume </b><a NAME="E1:79_1"/><i><font color="Green">E24</font></i>: 
<font color="Maroon">X</font> <a href="pboole.html#K3" target="_self">/\</a> <font color="Maroon">Y</font> <a href="pboole.html#R6" target="_self">=</a>  <a href="pboole.html#K1" target="_self">[0]</a> <font color="Maroon">I</font>
 ;<br/><b>thus </b><font color="Maroon">X</font> <a href="pboole.html#K4" target="_self">\</a> <font color="Maroon">Y</font> = 
<font color="Maroon">X</font> <a href="pboole.html#K4" target="_self">\</a> <span class="p1">(<span class="default"><font color="Maroon">X</font> <a href="pboole.html#K3" target="_self">/\</a> <font color="Maroon">Y</font></span>)</span>
<b>by </b><i/>
<br/>.= 
<font color="Maroon">X</font>
<b>by </b><i>, </i>
;<br/></div>
<b>end;</b></div>

<b>thus </b><a NAME="E2:79"/>
( <font color="Maroon">X</font> <a href="pboole.html#K4" target="_self">\</a> <font color="Maroon">Y</font> <a href="pboole.html#R6" target="_self">=</a> <font color="Maroon">X</font> implies <font color="Maroon">X</font> <a href="pboole.html#K3" target="_self">/\</a> <font color="Maroon">Y</font> <a href="pboole.html#R6" target="_self">=</a>  <a href="pboole.html#K1" target="_self">[0]</a> <font color="Maroon">I</font> )
 <b>by </b><i/>;<br/>


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