<?xml version="1.0"?>
<div class="add">

<b>let </b><font color="Maroon">S1</font> be  non <a href="struct_0.html#V3">empty</a>  <a href="msualg_1.html#L1">ManySortedSign</a> ;<br/><b>let </b><font color="Maroon">S2</font> be  non <a href="struct_0.html#V3">empty</a> non <a href="msualg_1.html#V2">void</a> <a href="msafree2.html#V2">Circuit-like</a>  <a href="msualg_1.html#L1">ManySortedSign</a> , <font color="Maroon">S</font> be  non <a href="struct_0.html#V3">empty</a> non <a href="msualg_1.html#V2">void</a> <a href="msafree2.html#V2">Circuit-like</a>  <a href="msualg_1.html#L1">ManySortedSign</a> ;<br/>



<b>assume </b><a NAME="E1:29"/><i><font color="Green">E24</font></i>: 
<font color="Maroon">S</font> <a href="hidden.html#R1">=</a> <font color="Maroon">S1</font> <a href="circcomb.html#K3" target="_self">+*</a> <font color="Maroon">S2</font>
 ;<br/>

<b>let </b><font color="Maroon">v2</font> be   <a href="msafree2.html#NM1">Vertex</a> of <font color="Maroon">S2</font>;<br/>

<b>assume </b><a NAME="E2:29"/><i><font color="Green">E33</font></i>: 
<font color="Maroon">v2</font> <a href="hidden.html#R2">in</a>  <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S2</font>
 ;<br/>

<b>let </b><font color="Maroon">v</font> be   <a href="msafree2.html#NM1">Vertex</a> of <font color="Maroon">S</font>;<br/>

<b>assume </b><a NAME="E3:29"/><i><font color="Green">E38</font></i>: 
<font color="Maroon">v2</font> <a href="hidden.html#R1">=</a> <font color="Maroon">v</font>
 ;<br/>

<a NAME="E4:29"/>
( the <a href="msualg_1.html#U3">ResultSort</a> of <font color="Maroon">S</font> <a href="hidden.html#R1">=</a> the <a href="msualg_1.html#U3">ResultSort</a> of <font color="Maroon">S1</font> <a href="funct_4.html#K1">+*</a> the <a href="msualg_1.html#U3">ResultSort</a> of <font color="Maroon">S2</font> &amp;  <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S2</font> <a href="hidden.html#R1">=</a>  <a href="relat_1.html#K2">rng</a> the <a href="msualg_1.html#U3">ResultSort</a> of <font color="Maroon">S2</font> &amp;  <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S</font> <a href="hidden.html#R1">=</a>  <a href="relat_1.html#K2">rng</a> the <a href="msualg_1.html#U3">ResultSort</a> of <font color="Maroon">S</font> )
 
<b>by </b><i>, </i>;<br/>
<a NAME="E5:29"/><b>then </b><i><font color="Green">E42</font></i>: 
 <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S2</font> <a href="tarski.html#R1">c=</a>  <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S</font>
 
<b>by </b><i><a class="ref" href="funct_4.html#T19">FUNCT_4:19</a></i>;<br/>
<b>hence </b><a NAME="E6:29"/>
<font color="Maroon">v</font> <a href="hidden.html#R2">in</a>  <a href="msafree2.html#K4">InnerVertices</a> <font color="Maroon">S</font>
 <b>by </b><i>, </i>;<br/>

<a NAME="E7:29"/><i><font color="Green">E43</font></i>: 
(  <a href="msualg_1.html#K2">the_result_sort_of</a> <span class="p1">(<span class="default"><a href="msafree2.html#K5">action_at</a> <font color="Maroon">v2</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">v2</font> &amp;  <a href="msualg_1.html#K2">the_result_sort_of</a> <span class="p1">(<span class="default"><a href="msafree2.html#K5">action_at</a> <font color="Maroon">v</font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">v</font> )
 
<b>by </b><i>, , , <a class="ref" href="msafree2.html#D7">MSAFREE2:def 7</a></i>;<br/>
<a NAME="E8:29"/>
( the <a href="msualg_1.html#U1">OperSymbols</a> of <font color="Maroon">S</font> <a href="hidden.html#R1">=</a> the <a href="msualg_1.html#U1">OperSymbols</a> of <font color="Maroon">S1</font> <a href="xboole_0.html#K2">\/</a> the <a href="msualg_1.html#U1">OperSymbols</a> of <font color="Maroon">S2</font> &amp;  <a href="msafree2.html#K5">action_at</a> <font color="Maroon">v2</font> <a href="hidden.html#R2">in</a> the <a href="msualg_1.html#U1">OperSymbols</a> of <font color="Maroon">S2</font> )
 
<b>by </b><i>, , </i>;<br/>
<b>then reconsider </b><font color="Maroon">o</font> =  <a href="msafree2.html#K5">action_at</a> <font color="Maroon">v2</font> as   <a href="msualg_1.html#NM2">OperSymbol</a> of <font color="Maroon">S</font> <b>by </b><i><a class="ref" href="xboole_0.html#D2">XBOOLE_0:def 2</a></i>;<br/>
<a NAME="E10:29"/>
<font color="Maroon">v</font> <a href="hidden.html#R1">=</a>  <a href="msualg_1.html#K2">the_result_sort_of</a> <font color="Maroon">o</font>
 
<b>by </b><i>, , , </i>;<br/>
<b>hence </b><a NAME="E11:29"/>
 <a href="msafree2.html#K5">action_at</a> <font color="Maroon">v</font> <a href="hidden.html#R1">=</a>  <a href="msafree2.html#K5">action_at</a> <font color="Maroon">v2</font>
 <b>by </b><i>, , , <a class="ref" href="msafree2.html#D7">MSAFREE2:def 7</a></i>;<br/>


</div>
