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<b>let </b><font color="Maroon">P</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">m</font> be    <a href="pnproc_1.html#M1" target="_self">marking</a> of <font color="Maroon">P</font>;<br/>



<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="30_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">p</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>assume </b><a NAME="E1:30_1"/>
<font color="Maroon">p</font> <a href="hidden.html#R2">in</a> <font color="Maroon">P</font>
 ;<br/><a NAME="E2:30_1"/><b>then </b>
<span class="p1">(<span class="default"><a href="pnproc_1.html#K3" target="_self">{$}</a> <font color="Maroon">P</font></span>)</span> <a href="pnproc_1.html#K2" target="_self">.</a> <font color="Maroon">p</font> <a href="hidden.html#R1">=</a> 0
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E3:30_1"/>
<font color="Maroon">m</font> <a href="pnproc_1.html#K2" target="_self">.</a> <font color="Maroon">p</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">m</font> <a href="pnproc_1.html#K2" target="_self">.</a> <font color="Maroon">p</font></span>)</span> <a href="nat_1.html#K1">+</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="pnproc_1.html#K3" target="_self">{$}</a> <font color="Maroon">P</font></span>)</span> <a href="pnproc_1.html#K2" target="_self">.</a> <font color="Maroon">p</font></span>)</span>
 ;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E2:30"/>
<font color="Maroon">m</font> <a href="pnproc_1.html#K4" target="_self">+</a> <span class="p1">(<span class="default"><a href="pnproc_1.html#K3" target="_self">{$}</a> <font color="Maroon">P</font></span>)</span> <a href="pnproc_1.html#R1" target="_self">=</a> <font color="Maroon">m</font>
 <b>by </b><i/>;<br/>


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