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<a NAME="E1:19_1_1"/>
 <a href="relat_1.html#K2">rng</a> <span class="p1">(<span class="default"><a href="finseq_2.html#K1">idseq</a> 2</span>)</span> <a href="tarski.html#R1">c=</a>  <a href="setwop_2.html#K2">Seg</a> 2
 
<b>by </b><i><a class="ref" href="relset_1.html#T12">RELSET_1:12</a></i>;<br/>
<b>then reconsider </b><font color="Maroon">f</font> =  <a href="finseq_2.html#K1">idseq</a> 2 as    <a href="finseq_1.html#M2">FinSequence</a> of  <a href="setwop_2.html#K2">Seg</a> 2 <b>by </b><i><a class="ref" href="finseq_1.html#D4">FINSEQ_1:def 4</a></i>;<br/>
<b>reconsider </b><font color="Maroon">g</font> = <span class="p1"><a href="finseq_4.html#K2">&lt;*</a><span class="default">2,1</span><a href="finseq_4.html#K2">*&gt;</a></span> as   <a href="funct_2.html#NM2">Permutation</a> of  <a href="setwop_2.html#K2">Seg</a> 2 <b>by </b><i>, <a class="ref" href="matrix_2.html#D11">MATRIX_2:def 11</a></i>;<br/>
<a NAME="E4:19_1_1"/>
for <font color="Olive">l</font> being  <a href="struct_0.html#NM7">FinSequence</a> of <span class="p1">(<span class="default"><a href="matrix_2.html#K13">Group_of_Perm</a> 2</span>)</span>  holds <br/>(  not <span class="p1">(<span class="default"><a href="finseq_1.html#K3">len</a> <font color="Olive">l</font></span>)</span> <a href="nat_1.html#K6">mod</a> 2 <a href="hidden.html#R1">=</a> 0 or  not <font color="Maroon">g</font> <a href="hidden.html#R1">=</a>  <a href="group_4.html#K3">Product</a> <font color="Olive">l</font> or  ex <font color="Olive">i</font> being  <a href="nat_1.html#NM1">Nat</a> st <br/>( <font color="Olive">i</font> <a href="hidden.html#R2">in</a>  <a href="setwop_2.html#K3">dom</a> <font color="Olive">l</font> &amp; ( for <font color="Olive">q</font> being   <a href="matrix_2.html#M3">Element</a> of  <a href="matrix_2.html#K12">Permutations</a> 2  holds <br/>(  not <font color="Olive">l</font> <a href="funct_1.html#K1">.</a> <font color="Olive">i</font> <a href="hidden.html#R1">=</a> <font color="Olive">q</font> or  not <font color="Olive">q</font> <a href="matrix_2.html#NR1" target="_self">is_transposition</a>  ) ) ) )
 
<b>by </b><i><a class="ref" href="matrix_7.html#T11">MATRIX_7:11</a>, </i>;<br/>
<a NAME="E5:19_1_1"/><b>then </b>
not <font color="Maroon">g</font> is <a href="matrix_2.html#V3">even</a>
 
<b>by </b><i><a class="ref" href="matrix_2.html#D15">MATRIX_2:def 15</a></i>;<br/>
<b>hence </b><a NAME="E6:19_1_1"/>
not for <font color="Olive">b<sub>1</sub></font> being  <a href="funct_2.html#NM2">Permutation</a> of  <a href="setwop_2.html#K2">Seg</a> 2 holds  <font color="Olive">b<sub>1</sub></font> is <a href="matrix_2.html#V3">even</a>
 ;<br/>


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