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<b>let </b><font color="Maroon" title="c1">f</font> be   <a href="finseq_1.html#NM1" title="FINSEQ_1:NM.1">FinSequence</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a> implies  <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a> )</span><br/>

<b>assume </b><a NAME="E1:21"/><i><font color="Green" title="E11">A1</font></i>: 
<font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide">  <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a></span><br/>

<a NAME="E2:21"/><i><font color="Green" title="E12">A2</font></i>: 
 <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c1">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <span class="p1">(<span class="default"><a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font></span>)</span>
 
<b>by </b><i><a class="ref" href="finseq_5.html#D3" title="FINSEQ_5:def.3">FINSEQ_5:def 3</a></i>;<br/>
<div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="21_1"><b>per </b></a><a class="txt" onclick="hs(this)" href="javascript:()"><b>cases </b></a><span class="hide"><a NAME="E1:21_1"/>
(  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c1">f</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> 2 or  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c1">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 2 )
 </span>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="21_1_1"><b>suppose </b></a><a NAME="E1:21_1_1"/><i><font color="Green" title="E13">A3</font></i>: 
 <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c1">f</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a> 2
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide">  <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a></span><br/><div class="add"><a NAME="E2:21_1_1"/><b>then </b>
<font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V2" title="JORDAN23:attr.2">weakly-one-to-one</a>
 <b>by </b><i><a class="txt" href="jordan23.html#E1:21"><i><font color="Green" title="E11">A1</font></i></a>, <a class="ref" href="jordan23.html#T7" target="_self" title="JORDAN23:th.7">Th7</a></i>;<br/><a NAME="E3:21_1_1"/><b>then </b>
 <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V2" title="JORDAN23:attr.2">weakly-one-to-one</a>
 <b>by </b><i><a class="ref" href="jordan23.html#T9" target="_self" title="JORDAN23:th.9">Th9</a></i>;<br/><b>hence </b><a NAME="E4:21_1_1"/>
 <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a>
 <b>by </b><i><a class="txt" href="jordan23.html#E2:21"><i><font color="Green" title="E12">A2</font></i></a>, <a class="txt" href="jordan23.html#E1:21_1_1"><i><font color="Green" title="E13">A3</font></i></a>, <a class="ref" href="jordan23.html#T7" target="_self" title="JORDAN23:th.7">Th7</a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/></div><b>end;</b></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="21_1_2"><b>suppose </b></a><a NAME="E1:21_1_2"/>
 <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c1">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 2
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide">  <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a></span><br/><div class="add"><b>hence </b><a NAME="E2:21_1_2"/>
 <a href="finseq_5.html#K3" title="FINSEQ_5:func.3">Rev</a> <font color="Maroon" title="c1">f</font> is <a href="jordan23.html#V3" title="JORDAN23:attr.3">poorly-one-to-one</a>
 <b>by </b><i><a class="txt" href="jordan23.html#E2:21"><i><font color="Green" title="E12">A2</font></i></a>, <a class="ref" href="jordan23.html#D3" target="_self" title="JORDAN23:def.3">Def3</a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/></div><b>end;</b></div></div><b>end;</b></div>

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