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<b>let </b><font color="Maroon" title="c1">G1</font>, <font color="Maroon" title="c2">G2</font> be   <a href="glib_000.html#NM2" title="GLIB_000:NM.2">_Graph</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( <font color="Maroon" title="c1">G1</font> <a href="glib_000.html#R5" title="GLIB_000:pred.5">==</a> <font color="Maroon" title="c2">G2</font> &amp; <font color="Maroon" title="c1">G1</font> is <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a> implies <font color="Maroon" title="c2">G2</font> is <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a> )</span><br/>



<b>assume </b><a NAME="E1:77"/><i><font color="Green" title="E46">A1</font></i>: 
( <font color="Maroon" title="c1">G1</font> <a href="glib_000.html#R5" title="GLIB_000:pred.5">==</a> <font color="Maroon" title="c2">G2</font> &amp; <font color="Maroon" title="c1">G1</font> is <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a> )
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> <font color="Maroon" title="c2">G2</font> is <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a></span><br/>

<b>then reconsider </b><font color="Maroon" title="c3">G1'</font> = <font color="Maroon" title="c1">G1</font> as  <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a> <a href="glib_000.html#NM2" title="GLIB_000:NM.2">_Graph</a> ;<br/>
<a NAME="E3:77"/>
<font color="Maroon" title="c2">G2</font> is    <a href="glib_000.html#M2" title="GLIB_000:mode.2">Subgraph</a> of <font color="Maroon" title="c3">G1'</font>
 
<b>by </b><i><a class="txt" href="glib_002.html#E1:77"><i><font color="Green" title="E46">A1</font></i></a>, <a class="ref" href="glib_000.html#T90" title="GLIB_000:th.90">GLIB_000:90</a></i>;<br/>
<b>hence </b><a NAME="E4:77"/>
<font color="Maroon" title="c2">G2</font> is <a href="glib_002.html#V2" title="GLIB_002:attr.2">acyclic</a>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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