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<div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="31_1_1_1"><b>per </b></a><a class="txt" onclick="hs(this)" href="javascript:()"><b>cases </b></a><span class="hide"><a NAME="E1:31_1_1_1"/>
( ( 1 <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">i</font> &amp; <font color="Maroon">i</font> <a href="xxreal_0.html#NR3" target="_self">&lt;</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font> ) or  not 1 <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">i</font> or  not <font color="Maroon">i</font> <a href="xxreal_0.html#NR3" target="_self">&lt;</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font> )
 </span>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="31_1_1_1_1"><b>suppose </b></a><a NAME="E1:31_1_1_1_1"/><i><font color="Green">E42</font></i>: 
( 1 <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">i</font> &amp; <font color="Maroon">i</font> <a href="xxreal_0.html#NR3" target="_self">&lt;</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font> )
 ;<br/><div class="add"><a NAME="E2:31_1_1_1_1"/><b>then </b><i><font color="Green">E43</font></i>: 
 <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> <a href="hidden.html#R1">=</a>  <a href="jordan7.html#K1">Segment</a> <span class="p1">(<span class="default"><font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <font color="Maroon">i</font></span>)</span>,<span class="p1">(<span class="default"><font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <span class="p2">(<span class="default"><font color="Maroon">i</font> <a href="nat_1.html#K1">+</a> 1</span>)</span></span>)</span>,<font color="Maroon">C</font>
 <b>by </b><i/>;<br/><a NAME="E3:31_1_1_1_1"/>
 <a href="jordan6.html#R1">LE</a> <font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <font color="Maroon">i</font>,<font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <span class="p1">(<span class="default"><font color="Maroon">i</font> <a href="nat_1.html#K1">+</a> 1</span>)</span>,<font color="Maroon">C</font>
 <b>by </b><i>, </i>;<br/><b>hence </b><a NAME="E4:31_1_1_1_1"/>
( not  <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> is <a href="xboole_0.html#V1">empty</a> &amp;  <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> is <a href="compts_1.html#V6">compact</a> )
 <b>by </b><i>, , <a class="ref" href="jordan7.html#T6">JORDAN7:6</a></i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="31_1_1_1_2"><b>suppose </b></a><a NAME="E1:31_1_1_1_2"/>
(  not 1 <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">i</font> or  not <font color="Maroon">i</font> <a href="xxreal_0.html#NR3" target="_self">&lt;</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font> )
 ;<br/><div class="add"><a NAME="E2:31_1_1_1_2"/><b>then </b><i><font color="Green">E44</font></i>: 
 <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> <a href="hidden.html#R1">=</a>  <a href="jordan7.html#K1">Segment</a> <span class="p1">(<span class="default"><font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <span class="p2">(<span class="default"><a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font></span>)</span></span>)</span>,<span class="p1">(<span class="default"><font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> 1</span>)</span>,<font color="Maroon">C</font>
 <b>by </b><i/>;<br/><a NAME="E3:31_1_1_1_2"/>
8 <a href="xxreal_0.html#R1">&lt;=</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font>
 <b>by </b><i/>;<br/><a NAME="E4:31_1_1_1_2"/><b>then </b>
1 <a href="xxreal_0.html#R1">&lt;=</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font>
 <b>by </b><i><a class="ref" href="xxreal_0.html#T2">XXREAL_0:2</a></i>;<br/><a NAME="E5:31_1_1_1_2"/><b>then </b><i><font color="Green">E45</font></i>: 
<font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> <span class="p1">(<span class="default"><a href="finseq_1.html#K3">len</a> <font color="Maroon">S</font></span>)</span> <a href="hidden.html#R2">in</a> <font color="Maroon">C</font>
 <b>by </b><i/>;<br/><a NAME="E6:31_1_1_1_2"/>
<font color="Maroon">S</font> <a href="finseq_4.html#K4">/.</a> 1 <a href="hidden.html#R1">=</a>  <a href="pscomp_1.html#K27">W-min</a> <font color="Maroon">C</font>
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E7:31_1_1_1_2"/>
( not  <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> is <a href="xboole_0.html#V1">empty</a> &amp;  <a href="jordan_a.html#K2" target="_self">Segm</a> <font color="Maroon">S</font>,<font color="Maroon">i</font> is <a href="compts_1.html#V6">compact</a> )
 <b>by </b><i>, , , <a class="ref" href="jordan16.html#T23">JORDAN16:23</a></i>;<br/></div><b>end;</b></div></div><b>end;</b></div>

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