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<b>let </b><font color="Maroon" title="c1">ND</font> be  non <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>let </b><font color="Maroon" title="c2">y1</font>, <font color="Maroon" title="c3">y2</font>, <font color="Maroon" title="c4">y3</font>, <font color="Maroon" title="c5">y4</font> be    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">ND</font>;<br/>









<b>set </b><font color="Maroon" title="c6">s</font> = <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span>;<br/>
<a NAME="E1:95"/>
(  <a href="finseq_1.html#K4" title="FINSEQ_1:func.4">dom</a> <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="enumset1.html#K2" title="ENUMSET1:func.2">{</a><span class="default">1,2,3,4</span><a href="enumset1.html#K2" title="ENUMSET1:func.2">}</a></span> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> 1 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">y1</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> 2 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">y2</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> 3 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">y3</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> 4 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">y4</font> &amp; 1 <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <span class="p1"><a href="enumset1.html#K2" title="ENUMSET1:func.2">{</a><span class="default">1,2,3,4</span><a href="enumset1.html#K2" title="ENUMSET1:func.2">}</a></span> &amp; 2 <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <span class="p1"><a href="enumset1.html#K2" title="ENUMSET1:func.2">{</a><span class="default">1,2,3,4</span><a href="enumset1.html#K2" title="ENUMSET1:func.2">}</a></span> &amp; 3 <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <span class="p1"><a href="enumset1.html#K2" title="ENUMSET1:func.2">{</a><span class="default">1,2,3,4</span><a href="enumset1.html#K2" title="ENUMSET1:func.2">}</a></span> &amp; 4 <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <span class="p1"><a href="enumset1.html#K2" title="ENUMSET1:func.2">{</a><span class="default">1,2,3,4</span><a href="enumset1.html#K2" title="ENUMSET1:func.2">}</a></span> )
 
<b>by </b><i><a class="ref" href="finseq_4.html#T91" target="_self" title="FINSEQ_4:th.91">Th91</a>, <a class="ref" href="finseq_4.html#T92" target="_self" title="FINSEQ_4:th.92">Th92</a>, <a class="ref" href="finseq_3.html#T2" title="FINSEQ_3:th.2">FINSEQ_3:2</a></i>;<br/>
<b>hence </b><a NAME="E2:95"/>
( <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="finseq_4.html#K4" title="FINSEQ_4:func.4">/.</a> 1 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">y1</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="finseq_4.html#K4" title="FINSEQ_4:func.4">/.</a> 2 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">y2</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="finseq_4.html#K4" title="FINSEQ_4:func.4">/.</a> 3 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">y3</font> &amp; <span class="p1"><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">y1</font>,<font color="Maroon" title="c3">y2</font>,<font color="Maroon" title="c4">y3</font>,<font color="Maroon" title="c5">y4</font></span><a href="finseq_4.html#K10" title="FINSEQ_4:func.10">*&gt;</a></span> <a href="finseq_4.html#K4" title="FINSEQ_4:func.4">/.</a> 4 <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">y4</font> )
 <b>by </b><i><a class="ref" href="finseq_4.html#D4" target="_self" title="FINSEQ_4:def.4">Def4</a></i>;<br/>


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