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<b>let </b><font color="Maroon">n</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/><b>let </b><font color="Maroon">K</font> be   <a href="vectsp_1.html#NM2">Field</a>;<br/><b>let </b><font color="Maroon">p</font> be    <a href="matrix_2.html#M3">Element</a> of  <a href="matrix_2.html#K12">Permutations</a> <font color="Maroon">n</font>;<br/><b>let </b><font color="Maroon">x</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">K</font>;<br/>







<b>assume </b><a NAME="E1:35"/><i><font color="Green">E39</font></i>: 
<font color="Maroon">n</font> <a href="xxreal_0.html#NR2" target="_self">&gt;=</a> 1
 ;<br/>

<a NAME="E2:35"/><i><font color="Green">E40</font></i>: 
 <a href="matrix_2.html#K11">len</a> <span class="p1">(<span class="default"><a href="matrix_2.html#K12">Permutations</a> <font color="Maroon">n</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">n</font>
 
<b>by </b><i><a class="ref" href="matrix_2.html#T20">MATRIX_2:20</a></i>;<br/>
<b>reconsider </b><font color="Maroon">pf</font> = <font color="Maroon">p</font> as   <a href="funct_2.html#NM2">Permutation</a> of  <a href="finseq_1.html#K2">Seg</a> <font color="Maroon">n</font> <b>by </b><i><a class="ref" href="matrix_2.html#D11">MATRIX_2:def 11</a></i>;<br/>
<div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1"><b>per </b></a><a class="txt" onclick="hs(this)" href="javascript:()"><b>cases </b></a><span class="hide"><a NAME="E1:35_1"/>
( <font color="Maroon">p</font> is <a href="matrix_2.html#V3">even</a> or  not <font color="Maroon">p</font> is <a href="matrix_2.html#V3">even</a> )
 </span>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1_1"><b>suppose </b></a><a NAME="E1:35_1_1"/><i><font color="Green">E42</font></i>: 
<font color="Maroon">p</font> is <a href="matrix_2.html#V3">even</a>
 ;<br/><div class="add"><a NAME="E2:35_1_1"/><b>then </b><i><font color="Green">E43</font></i>: 
 <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<font color="Maroon">p</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x</font>
 <b>by </b><i><a class="ref" href="matrix_2.html#D16">MATRIX_2:def 16</a></i>;<br/><a NAME="E3:35_1_1"/>
<font color="Maroon">pf</font> <a href="funct_2.html#K2">"</a>  is <a href="matrix_2.html#V3">even</a>
 <b>by </b><i>, , , <a class="txt" href="matrix_7.html#E1"><i><font color="Green">Lemma34</font></i></a></i>;<br/><b>hence </b><a NAME="E4:35_1_1"/>
 <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<font color="Maroon">p</font> <a href="hidden.html#R1">=</a>  <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="matrix_7.html#K3" target="_self">"</a> </span>)</span>
 <b>by </b><i>, <a class="ref" href="matrix_2.html#D16">MATRIX_2:def 16</a>, <a class="txt" href="matrix_7.html#E1"><i><font color="Green">Lemma34</font></i></a></i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1_2"><b>suppose </b></a><a NAME="E1:35_1_2"/><i><font color="Green">E44</font></i>: 
not <font color="Maroon">p</font> is <a href="matrix_2.html#V3">even</a>
 ;<br/><div class="add"><a NAME="E2:35_1_2"/><b>then </b><i><font color="Green">E45</font></i>: 
 <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<font color="Maroon">p</font> <a href="hidden.html#R1">=</a>  <a href="rlvect_1.html#K5">-</a> <font color="Maroon">x</font>
 <b>by </b><i><a class="ref" href="matrix_2.html#D16">MATRIX_2:def 16</a></i>;<br/><a NAME="E3:35_1_2"/>
not <font color="Maroon">p</font> <a href="matrix_7.html#K3" target="_self">"</a>  is <a href="matrix_2.html#V3">even</a>
 <b>by </b><i>, , </i>;<br/><b>hence </b><a NAME="E4:35_1_2"/>
 <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<font color="Maroon">p</font> <a href="hidden.html#R1">=</a>  <a href="matrix_2.html#K14">-</a> <font color="Maroon">x</font>,<span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="matrix_7.html#K3" target="_self">"</a> </span>)</span>
 <b>by </b><i>, <a class="ref" href="matrix_2.html#D16">MATRIX_2:def 16</a></i>;<br/></div><b>end;</b></div></div><b>end;</b></div>

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