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<b>let </b><font color="Maroon">i</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/><b>let </b><font color="Maroon">j</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/><b>let </b><font color="Maroon">n</font> be    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K5">NAT</a> ;<br/>





<a NAME="E1:35"/><i><font color="Green">E33</font></i>: 
0 <a href="xxreal_0.html#NR3" target="_self">&lt;</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font>
 
<b>by </b><i><a class="ref" href="power.html#T39">POWER:39</a></i>;<br/>
<a NAME="E2:35"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="xxreal_0.html#NR3" target="_self">&lt;</a> <span class="p1">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1
 
<b>by </b><i><a class="ref" href="nat_1.html#T46">NAT_1:46</a></i>;<br/>
<a NAME="E3:35"/><b>then </b><i><font color="Green">E35</font></i>: 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="xxreal_0.html#R1">&lt;=</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font>
 
<b>by </b><i><a class="ref" href="nat_1.html#T38">NAT_1:38</a></i>;<br/>
<b>set </b><font color="Maroon">CV</font> = <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span>;<br/>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="35_1"><b>now </b></a><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1_1"><b>per </b></a><a class="txt" onclick="hs(this)" href="javascript:()"><b>cases </b></a><span class="hide"><a NAME="E1:35_1_1"/>
( <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="hidden.html#R1">=</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font> or <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="xxreal_0.html#NR3" target="_self">&lt;</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font> )
 </span><b>by </b><i>, <a class="ref" href="xxreal_0.html#T1">XXREAL_0:1</a></i>;<br/><div class="add"><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1_1_1"><b>suppose </b></a><a NAME="E1:35_1_1_1"/>
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="hidden.html#R1">=</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font>
 ;<br/><div class="add"><a NAME="E2:35_1_1_1"/><b>then </b>
 <a href="idea_1.html#K8" target="_self">ChangeVal_2</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p3">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span></span>)</span>,<font color="Maroon">n</font> <a href="hidden.html#R1">=</a> 0
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E3:35_1_1_1"/>
 <a href="idea_1.html#K9" target="_self">MUL_MOD</a> <font color="Maroon">i</font>,<font color="Maroon">j</font>,<font color="Maroon">n</font> <a href="idea_1.html#R1" target="_self">is_expressible_by</a> <font color="Maroon">n</font>
 <b>by </b><i>, </i>;<br/></div><b>end;</b></div><div><a class="txt" onclick="hsNdiv(this)" href="javascript:()" title="35_1_1_2"><b>suppose </b></a><a NAME="E1:35_1_1_2"/><i><font color="Green">E36</font></i>: 
<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span> <a href="xxreal_0.html#NR3" target="_self">&lt;</a> 2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font>
 ;<br/><div class="add"><a NAME="E2:35_1_1_2"/><b>then </b>
 <a href="idea_1.html#K8" target="_self">ChangeVal_2</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><span class="p3">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p3">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p2">(<span class="default"><span class="p3">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span></span>)</span>,<font color="Maroon">n</font> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">i</font>,<font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K2">*</a> <span class="p2">(<span class="default"><a href="idea_1.html#K7" target="_self">ChangeVal_1</a> <font color="Maroon">j</font>,<font color="Maroon">n</font></span>)</span></span>)</span> <a href="nat_1.html#K6">mod</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default">2 <a href="series_1.html#K3">to_power</a> <font color="Maroon">n</font></span>)</span> <a href="nat_1.html#K1">+</a> 1</span>)</span>
 <b>by </b><i/>;<br/><b>hence </b><a NAME="E3:35_1_1_2"/>
 <a href="idea_1.html#K9" target="_self">MUL_MOD</a> <font color="Maroon">i</font>,<font color="Maroon">j</font>,<font color="Maroon">n</font> <a href="idea_1.html#R1" target="_self">is_expressible_by</a> <font color="Maroon">n</font>
 <b>by </b><i>, </i>;<br/></div><b>end;</b></div></div><b>end;</b></div></div><b>end;</b></div>
<b>hence </b><a NAME="E5:35"/>
 <a href="idea_1.html#K9" target="_self">MUL_MOD</a> <font color="Maroon">i</font>,<font color="Maroon">j</font>,<font color="Maroon">n</font> <a href="idea_1.html#R1" target="_self">is_expressible_by</a> <font color="Maroon">n</font>
 ;<br/>


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