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



<a NAME="E1:56"/><i><font color="Green">E39</font></i>: 
 <a href="relat_1.html#K2">rng</a> <span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><a href="relat_1.html#K2">rng</a> <font color="Maroon">p</font></span>)</span> <a href="xboole_0.html#K2">\/</a> <span class="p1">(<span class="default"><a href="relat_1.html#K2">rng</a> <font color="Maroon">q</font></span>)</span>
 
<b>by </b><i><a class="ref" href="finseq_1.html#T44">FINSEQ_1:44</a></i>;<br/>
<b>thus </b><a NAME="E2:56"/>
( <font color="Maroon">p</font> is <a href="trees_3.html#V5" target="_self">FinTree-yielding</a> &amp; <font color="Maroon">q</font> is <a href="trees_3.html#V5" target="_self">FinTree-yielding</a> implies <font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font> is <a href="trees_3.html#V5" target="_self">FinTree-yielding</a> )
 <div><a class="txt" onclick="hs2(this)" href="javascript:()" title="56_1"><b>proof </b></a><div class="add">

<b>assume </b><a NAME="E1:56_1"/>
(  <a href="relat_1.html#K2">rng</a> <font color="Maroon">p</font> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a> &amp;  <a href="relat_1.html#K2">rng</a> <font color="Maroon">q</font> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a> )
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="trees_3.html#D10" target="_self">TREES_3:def 10</a><br/>

<b>hence </b><a NAME="E2:56_1"/>
 <a href="relat_1.html#K2">rng</a> <span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font></span>)</span> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a>
 <b>by </b><i>, </i>; <i><font color="Red">:: according to </font></i><a class="ref" href="trees_3.html#D10" target="_self">TREES_3:def 10</a><br/>


</div><b>end;</b></div>

<b>assume </b><a NAME="E3:56"/><i><font color="Green">E40</font></i>: 
 <a href="relat_1.html#K2">rng</a> <span class="p1">(<span class="default"><font color="Maroon">p</font> <a href="finseq_1.html#K7">^</a> <font color="Maroon">q</font></span>)</span> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a>
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="trees_3.html#D10" target="_self">TREES_3:def 10</a><br/>

<b>hence </b><a NAME="E4:56"/>
 <a href="relat_1.html#K2">rng</a> <font color="Maroon">p</font> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a>
 <b>by </b><i>, </i>; <i><font color="Red">:: according to </font></i><a class="ref" href="trees_3.html#D10" target="_self">TREES_3:def 10</a><br/>

<b>thus </b><a NAME="E5:56"/>
 <a href="relat_1.html#K2">rng</a> <font color="Maroon">q</font> is <a href="trees_3.html#V2" target="_self">constituted-FinTrees</a>
 <b>by </b><i>, , </i>; <i><font color="Red">:: according to </font></i><a class="ref" href="trees_3.html#D10" target="_self">TREES_3:def 10</a><br/>


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