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<span class="kw">let </span><font color="Maroon" title="c1">Y</font> be   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font> &amp; <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font> &amp; <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font> )</span><br/>

<span class="kw">thus </span><span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> = 
 <a href="margrel1.html#K14" title="MARGREL1:func.14">'not'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span>
<span class="kw">by</span> <span class="lab"><a class="ref" href="bvfunc25.html#T73" target="_self" onmouseover="rs('bvfunc25/T73')" onmouseout="rh()">Th27</a></span>
<br/>.= 
 <a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font>
<span class="kw">by</span> <span class="lab"><a class="ref" href="bvfunc_1.html#T2" onmouseover="rs('bvfunc_1/T2')" onmouseout="rh()">BVFUNC_1:2</a></span>
; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font> &amp; <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font> )</span><br/>

<span class="kw">thus </span><a NAME="E2:77"/>
<span class="p1">(<span class="default"><a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="bvfunc25.html#T72" target="_self" onmouseover="rs('bvfunc25/T72')" onmouseout="rh()">Th26</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font></span><br/>

<span class="kw">thus </span><a NAME="E3:77"/>
<span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="bvfunc25.html#K6" title="BVFUNC25:func.6">'nor'</a> <span class="p1">(<span class="default"><a href="bvfunc_1.html#K12" title="BVFUNC_1:func.12">I_el</a> <font color="Maroon" title="c1">Y</font></span>)</span> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a>  <a href="bvfunc_1.html#K11" title="BVFUNC_1:func.11">O_el</a> <font color="Maroon" title="c1">Y</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="bvfunc25.html#T72" target="_self" onmouseover="rs('bvfunc25/T72')" onmouseout="rh()">Th26</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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