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<b>let </b><font color="Maroon">OAS</font> be   <a href="analoaf.html#NM1">OAffinSpace</a>;<br/><b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">OAS</font>;<br/><b>let </b><font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">OAS</font>;<br/><b>let </b><font color="Maroon">c</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">OAS</font>;<br/><b>let </b><font color="Maroon">d</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">OAS</font>;<br/><b>let </b><font color="Maroon">p</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">OAS</font>;<br/>











<b>assume </b><a NAME="E1:38"/><i><font color="Green">E29</font></i>: 
( <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="diraf.html#R2">'||'</a> <font color="Maroon">c</font>,<font color="Maroon">d</font> &amp; <font color="Maroon">a</font>,<font color="Maroon">c</font> <a href="diraf.html#R2">'||'</a> <font color="Maroon">b</font>,<font color="Maroon">d</font> &amp; not  <a href="diraf.html#R3">LIN</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<font color="Maroon">c</font> &amp;  <a href="diraf.html#R3">LIN</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>,<font color="Maroon">d</font> &amp;  <a href="diraf.html#R3">LIN</a> <font color="Maroon">p</font>,<font color="Maroon">b</font>,<font color="Maroon">c</font> )
 ;<br/>

<b>assume </b><a NAME="E2:38"/><i><font color="Green">E30</font></i>: 
 <a href="diraf.html#R3">LIN</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>,<font color="Maroon">b</font>
 ;<br/>

<a NAME="E3:38"/>
( <font color="Maroon">p</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">a</font> &amp;  <a href="diraf.html#R3">LIN</a> <font color="Maroon">p</font>,<font color="Maroon">a</font>,<font color="Maroon">a</font> )
 
<b>by </b><i>, <a class="ref" href="diraf.html#T37">DIRAF:37</a></i>;<br/>
<a NAME="E4:38"/><b>then </b>
( <font color="Maroon">a</font> <a href="hidden.html#NR2" target="_self">&lt;&gt;</a> <font color="Maroon">b</font> &amp;  <a href="diraf.html#R3">LIN</a> <font color="Maroon">a</font>,<font color="Maroon">b</font>,<font color="Maroon">d</font> &amp; <font color="Maroon">a</font>,<font color="Maroon">b</font> <a href="diraf.html#R2">'||'</a> <font color="Maroon">d</font>,<font color="Maroon">c</font> )
 
<b>by </b><i>, , <a class="ref" href="diraf.html#T27">DIRAF:27</a>, <a class="ref" href="diraf.html#T38">DIRAF:38</a></i>;<br/>
<b>hence </b><a NAME="E5:38"/>
contradiction
 <b>by </b><i>, <a class="ref" href="diraf.html#T39">DIRAF:39</a></i>;<br/>


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