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<span class="kw">let </span><font color="Maroon" title="c1">i</font> be    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="numbers.html#K5" title="NUMBERS:func.5">NAT</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  for <font color="Olive" title="b1">f</font> being    <a href="finseq_1.html#M2" title="FINSEQ_1:mode.2">FinSequence</a> of  the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <span class="p1">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> 2</span>)</span>  st <font color="Olive" title="b1">f</font> is  <a href="topreal1.html#V1" title="TOPREAL1:attr.1">special</a>  &amp; <font color="Olive" title="b1">f</font> is  <a href="sppol_1.html#V3" title="SPPOL_1:attr.3">alternating</a>  &amp; 1 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a> <font color="Maroon" title="c1">i</font> &amp; <font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 2 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a>  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Olive" title="b1">f</font> &amp;  not <!--HUMANRECFAILED-->(  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Olive" title="b1">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Olive" title="b1">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  ) holds <br/>(  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Olive" title="b1">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Olive" title="b1">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  )</span><br/><span class="kw">let </span><font color="Maroon" title="c2">f</font> be    <a href="finseq_1.html#M2" title="FINSEQ_1:mode.2">FinSequence</a> of  the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <span class="p1">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> 2</span>)</span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c2">f</font> is  <a href="topreal1.html#V1" title="TOPREAL1:attr.1">special</a>  &amp; <font color="Maroon" title="c2">f</font> is  <a href="sppol_1.html#V3" title="SPPOL_1:attr.3">alternating</a>  &amp; 1 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a> <font color="Maroon" title="c1">i</font> &amp; <font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 2 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a>  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c2">f</font> &amp;  not <!--HUMANRECFAILED-->(  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  ) implies (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  ) )</span><br/>



<span class="kw">assume </span><a NAME="E1:46"/><span class="lab"><font color="Green" title="E28">A1</font></span>: 
( <font color="Maroon" title="c2">f</font> is  <a href="topreal1.html#V1" title="TOPREAL1:attr.1">special</a>  &amp; <font color="Maroon" title="c2">f</font> is  <a href="sppol_1.html#V3" title="SPPOL_1:attr.3">alternating</a>  &amp; 1 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a> <font color="Maroon" title="c1">i</font> &amp; <font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 2 <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a>  <a href="finseq_1.html#K3" title="FINSEQ_1:func.3">len</a> <font color="Maroon" title="c2">f</font> )
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  ) or (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  ) )</span><br/>

<a NAME="E2:46"/><span class="kw">then </span>
(  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  not <!--HUMANRECFAILED-->(  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  ) implies (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  ) )
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="sppol_1.html#T32" target="_self" title="SPPOL_1:th.32">Th55</a></span>;<br/>
<span class="kw">hence </span><a NAME="E3:46"/>
( (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  ) or (  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<font color="Maroon" title="c1">i</font>) is  <a href="sppol_1.html#V1" title="SPPOL_1:attr.1">horizontal</a>  &amp;  <a href="topreal1.html#K2" title="TOPREAL1:func.2">LSeg</a> (<font color="Maroon" title="c2">f</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">i</font> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> 1</span>)</span>) is  <a href="sppol_1.html#V2" title="SPPOL_1:attr.2">vertical</a>  ) )
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:46"><span class="lab"><font color="Green" title="E28">A1</font></span></a>, <a class="ref" href="sppol_1.html#T19" target="_self" title="SPPOL_1:th.19">Th41</a>, <a class="ref" href="sppol_1.html#T33" target="_self" title="SPPOL_1:th.33">Th56</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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