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<b>consider </b><font color="Maroon">q</font> being  <a href="xboole_0.html#V1">empty</a>  <a href="graph_1.html#M2">Chain</a> of <font color="Maroon">G</font>;<br/>
<b>reconsider </b><font color="Maroon">q</font> = <font color="Maroon">q</font> as  <a href="funct_1.html#V2">V5</a>  <a href="graph_1.html#M2">Chain</a> of <font color="Maroon">G</font> ;<br/>
<b>take </b>
<font color="Maroon">q</font>
;<br/>

<b>consider </b><font color="Maroon">x</font> being    <a href="subset_1.html#M1">Element</a> of the <a href="graph_1.html#U1">Vertices</a> of <font color="Maroon">G</font>;<br/>
<b>reconsider </b><font color="Maroon">p</font> = <span class="p1"><a href="binarith.html#K11">&lt;*</a><span class="default"><font color="Maroon">x</font></span><a href="binarith.html#K11">*&gt;</a></span> as    <a href="finseq_1.html#M2">FinSequence</a> of the <a href="graph_1.html#U1">Vertices</a> of <font color="Maroon">G</font> ;<br/>
<b>take </b>
<font color="Maroon">p</font>
; <i><font color="Red">:: according to </font></i><a class="ref" href="graph_2.html#D10" target="_self">GRAPH_2:def 10</a><br/>

<b>thus </b><a NAME="E5:75_1_1"/>
<font color="Maroon">p</font> <a href="graph_2.html#R1" target="_self">is_vertex_seq_of</a> <font color="Maroon">q</font>
 <b>by </b><i/>;<br/>

<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">m</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/>



<b>assume </b><a NAME="E6:75_1_1"/>
( 1 <a href="xxreal_0.html#R1">&lt;=</a> <font color="Maroon">n</font> &amp; <font color="Maroon">n</font> <a href="xxreal_0.html#NR3" target="_self">&lt;</a> <font color="Maroon">m</font> &amp; <font color="Maroon">m</font> <a href="xxreal_0.html#R1">&lt;=</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">p</font> &amp; <font color="Maroon">p</font> <a href="funct_1.html#K1">.</a> <font color="Maroon">n</font> <a href="hidden.html#R1">=</a> <font color="Maroon">p</font> <a href="funct_1.html#K1">.</a> <font color="Maroon">m</font> )
 ;<br/>

<a NAME="E7:75_1_1"/><b>then </b>
( 1 <a href="xxreal_0.html#NR3" target="_self">&lt;</a> <font color="Maroon">m</font> &amp; <font color="Maroon">m</font> <a href="xxreal_0.html#R1">&lt;=</a> 1 )
 
<b>by </b><i><a class="ref" href="xxreal_0.html#T2">XXREAL_0:2</a>, <a class="ref" href="finseq_1.html#T56">FINSEQ_1:56</a></i>;<br/>
<b>hence </b><a NAME="E8:75_1_1"/>
( <font color="Maroon">n</font> <a href="hidden.html#R1">=</a> 1 &amp; <font color="Maroon">m</font> <a href="hidden.html#R1">=</a>  <a href="finseq_1.html#K3">len</a> <font color="Maroon">p</font> )
 ;<br/>


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