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<b>let </b><font color="Maroon">p</font> be   <a href="finseq_1.html#NM1">FinSequence</a>, <font color="Maroon">q</font> be   <a href="finseq_1.html#NM1">FinSequence</a>, <font color="Maroon">r</font> be   <a href="finseq_1.html#NM1">FinSequence</a>, <font color="Maroon">s</font> be   <a href="finseq_1.html#NM1">FinSequence</a>;<br/>

<b>assume </b><a NAME="E1:1"/><i><font color="Green">E28</font></i>: 
<font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font> <a href="hidden.html#R1">=</a> <font color="Maroon">s</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">r</font>
 ;<br/>

<a NAME="E2:1"/><b>then </b><i><font color="Green">E29</font></i>: 
<font color="Maroon">p</font> <a href="tarski.html#R1">is_a_prefix_of</a> <font color="Maroon">s</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">r</font>
 
<b>by </b><i><a class="ref" href="trees_1.html#T8">TREES_1:8</a></i>;<br/>
<a NAME="E3:1"/>
<font color="Maroon">s</font> <a href="tarski.html#R1">is_a_prefix_of</a> <font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font>
 
<b>by </b><i>, <a class="ref" href="trees_1.html#T8">TREES_1:8</a></i>;<br/>
<b>hence </b><a NAME="E4:1"/>
<font color="Maroon">p</font>,<font color="Maroon">s</font> <a href="xboole_0.html#R3">are_c=-comparable</a> 
 <b>by </b><i>, , <a class="ref" href="trees_2.html#T1">TREES_2:1</a></i>;<br/>


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