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<b>let </b><font color="Maroon" title="c1">a</font> be   <a href="int_1.html#NM1" title="INT_1:NM.1">Integer</a>;<br/><b>let </b><font color="Maroon" title="c2">p</font> be   <a href="newton.html#NM1" title="NEWTON:NM.1">Prime</a>;<br/><b>let </b><font color="Maroon" title="c3">b</font> be   <a href="int_1.html#NM1" title="INT_1:NM.1">Integer</a>;<br/>





<b>assume </b><a NAME="E1:39"/><i><font color="Green" title="E28">A1</font></i>: 
( <font color="Maroon" title="c2">p</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a> 2 &amp; <font color="Maroon" title="c1">a</font> <a href="int_2.html#K3" title="INT_2:func.3">gcd</a> <font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 &amp; <font color="Maroon" title="c3">b</font> <a href="int_2.html#K3" title="INT_2:func.3">gcd</a> <font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 )
 ;<br/>

<a NAME="E2:39"/><b>then </b>
(  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font>,<font color="Maroon" title="c1">a</font> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font> &amp;  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font>,<font color="Maroon" title="c3">b</font> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font> )
 
<b>by </b><i><a class="ref" href="int_5.html#T28" target="_self" title="INT_5:th.28">Th28</a></i>;<br/>
<a NAME="E3:39"/><b>then </b>
<span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><font color="Maroon" title="c3">b</font> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span></span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font>
 
<b>by </b><i><a class="ref" href="int_1.html#T39" title="INT_1:th.39">INT_1:39</a></i>;<br/>
<a NAME="E4:39"/><b>then </b>
<span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font>
 
<b>by </b><i><a class="ref" href="newton.html#T12" title="NEWTON:th.12">NEWTON:12</a></i>;<br/>
<a NAME="E5:39"/><b>then </b><i><font color="Green" title="E29">A2</font></i>: 
<span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span>,<span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font>
 
<b>by </b><i><a class="ref" href="int_1.html#T35" title="INT_1:th.35">INT_1:35</a></i>;<br/>
<a NAME="E6:39"/>
<span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span> <a href="int_2.html#K3" title="INT_2:func.3">gcd</a> <font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1
 
<b>by </b><i><a class="txt" href="int_5.html#E1:39"><i><font color="Green" title="E28">A1</font></i></a>, <a class="ref" href="wsierp_1.html#T11" title="WSIERP_1:th.11">WSIERP_1:11</a></i>;<br/>
<a NAME="E7:39"/><b>then </b>
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span> <a href="newton.html#K2" title="NEWTON:func.2">|^</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Maroon" title="c2">p</font> <a href="binarith.html#K3" title="BINARITH:func.3">-'</a> 1</span>)</span> <a href="nat_d.html#K3" title="NAT_D:func.3">div</a> 2</span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font>
 
<b>by </b><i><a class="txt" href="int_5.html#E1:39"><i><font color="Green" title="E28">A1</font></i></a>, <a class="ref" href="int_5.html#T28" target="_self" title="INT_5:th.28">Th28</a></i>;<br/>
<a NAME="E8:39"/><b>then </b>
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font>,<span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="int_1.html#R1" title="INT_1:pred.1">are_congruent_mod</a> <font color="Maroon" title="c2">p</font>
 
<b>by </b><i><a class="txt" href="int_5.html#E5:39"><i><font color="Green" title="E29">A2</font></i></a>, <a class="ref" href="int_1.html#T36" title="INT_1:th.36">INT_1:36</a></i>;<br/>
<a NAME="E9:39"/><b>then </b><i><font color="Green" title="E30">A3</font></i>: 
<font color="Maroon" title="c2">p</font> <a href="int_1.html#R2" title="INT_1:pred.2">divides</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p2">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K6" title="XCMPLX_0:func.6">-</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p2">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span></span>)</span>
 
<b>by </b><i><a class="ref" href="int_2.html#T19" title="INT_2:th.19">INT_2:19</a></i>;<br/>
<a NAME="E10:39"/><i><font color="Green" title="E31">A4</font></i>: 
( (  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 or  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1 ) &amp; (  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 or  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1 ) )
 
<b>by </b><i><a class="ref" href="int_5.html#T25" target="_self" title="INT_5:th.25">Th25</a></i>;<br/>
<div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="39_1"><b>per </b></a><a class="txt" onclick="hs(this)" href="javascript:()"><b>cases </b></a><span class="hide"><a NAME="E1:39_1"/>
(  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 or  <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1 )
 </span><b>by </b><i><a class="ref" href="int_5.html#T25" target="_self" title="INT_5:th.25">Th25</a></i>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="39_1_1"><b>suppose </b></a><a NAME="E1:39_1_1"/>
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1
 ;<br/><div class="add"><b>hence </b><a NAME="E2:39_1_1"/>
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span>
 <b>by </b><i><a class="txt" href="int_5.html#E1:39"><i><font color="Green" title="E28">A1</font></i></a>, <a class="txt" href="int_5.html#E9:39"><i><font color="Green" title="E30">A3</font></i></a>, <a class="txt" href="int_5.html#E10:39"><i><font color="Green" title="E31">A4</font></i></a>, <a class="ref" href="nat_d.html#T7" title="NAT_D:th.7">NAT_D:7</a></i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="39_1_2"><b>suppose </b></a><a NAME="E1:39_1_2"/><i><font color="Green" title="E32">A5</font></i>: 
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1
 ;<br/><div class="add"><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="39_1_2_1"><b>now </b></a><div class="add"><b>assume </b><a NAME="E1:39_1_2_1"/>
<span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1
 ;<br/><a NAME="E2:39_1_2_1"/><b>then </b>
<font color="Maroon" title="c2">p</font> <a href="int_1.html#R2" title="INT_1:pred.2">divides</a>  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 2
 <b>by </b><i><a class="txt" href="int_5.html#E9:39"><i><font color="Green" title="E30">A3</font></i></a>, <a class="txt" href="int_5.html#E10:39"><i><font color="Green" title="E31">A4</font></i></a>, <a class="txt" href="int_5.html#E1:39_1_2"><i><font color="Green" title="E32">A5</font></i></a></i>;<br/><a NAME="E3:39_1_2_1"/><b>then </b>
<font color="Maroon" title="c2">p</font> <a href="nat_d.html#R1" title="NAT_D:pred.1">divides</a> 2
 <b>by </b><i><a class="ref" href="int_2.html#T14" title="INT_2:th.14">INT_2:14</a></i>;<br/><b>hence </b><a NAME="E4:39_1_2_1"/>
contradiction
 <b>by </b><i><a class="txt" href="int_5.html#E1:39"><i><font color="Green" title="E28">A1</font></i></a>, <a class="ref" href="nat_d.html#T7" title="NAT_D:th.7">NAT_D:7</a></i>;<br/></div><b>end;</b></div><b>hence </b><a NAME="E3:39_1_2"/>
 <a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">a</font> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <font color="Maroon" title="c3">b</font></span>)</span>,<font color="Maroon" title="c2">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c1">a</font>,<font color="Maroon" title="c2">p</font></span>)</span> <a href="xcmplx_0.html#K3" title="XCMPLX_0:func.3">*</a> <span class="p1">(<span class="default"><a href="int_5.html#K2" title="INT_5:func.2">Lege</a> <font color="Maroon" title="c3">b</font>,<font color="Maroon" title="c2">p</font></span>)</span>
 <b>by </b><i><a class="txt" href="int_5.html#E1:39_1_2"><i><font color="Green" title="E32">A5</font></i></a></i>;<br/></div><b>end;</b></div></div><b>end;</b></div>

</div>
