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<b>let </b><font color="Maroon">c<sub>1</sub></font>, <font color="Maroon">c<sub>2</sub></font> be  non <a href="struct_0.html#V3">empty</a> <a href="lang1.html#V1">strict</a>  <a href="lang1.html#L1">DTConstrStr</a> ;<br/>

<b>assume </b><b>that </b><br/><a NAME="E1:15_1"/><i><font color="Green">E8</font></i>: 
( the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">F<sub>1</sub></font>() &amp; ( for <font color="Olive">b<sub>1</sub></font> being  <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>1</sub></font><br/>for <font color="Olive">b<sub>2</sub></font> being   <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> holds <br/>( <font color="Olive">b<sub>1</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Olive">b<sub>2</sub></font> iff <font color="Maroon">P<sub>1</sub></font>[<font color="Olive">b<sub>1</sub></font>,<font color="Olive">b<sub>2</sub></font>] ) ) )
 <b>and </b><br/><a NAME="E2:15_1"/><i><font color="Green">E9</font></i>: 
( the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">F<sub>1</sub></font>() &amp; ( for <font color="Olive">b<sub>1</sub></font> being  <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>2</sub></font><br/>for <font color="Olive">b<sub>2</sub></font> being   <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> holds <br/>( <font color="Olive">b<sub>1</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Olive">b<sub>2</sub></font> iff <font color="Maroon">P<sub>1</sub></font>[<font color="Olive">b<sub>1</sub></font>,<font color="Olive">b<sub>2</sub></font>] ) ) )
 ;<br/>

<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="15_1_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon">c<sub>3</sub></font>, <font color="Maroon">c<sub>4</sub></font> be    <a href="hidden.html#M1">set</a> ;<br/><div><b>hereby </b>
<div class="add"><b>assume </b><a NAME="E1:15_1_1_1"/><i><font color="Green">E10</font></i>: 
<span class="p1"><a href="tarski.html#K4">[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="tarski.html#K4">]</a></span> <a href="hidden.html#R2">in</a> the <a href="lang1.html#U1">Rules</a> of <font color="Maroon">c<sub>1</sub></font>
 ;<br/><a NAME="E2:15_1_1_1"/><b>then </b><i><font color="Green">E11</font></i>: 
( <font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R2">in</a> the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> &amp; <font color="Maroon">c<sub>4</sub></font> <a href="hidden.html#R2">in</a> the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> <a href="finseq_2.html#K3">*</a>  )
 <b>by </b><i><a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>5</sub></font> = <font color="Maroon">c<sub>3</sub></font> as   <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>1</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1_1_1"><i><font color="Green">E10</font></i></a>, <a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>6</sub></font> = <font color="Maroon">c<sub>4</sub></font> as    <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E2:15_1_1_1"><i><font color="Green">E11</font></i></a>, <a class="ref" href="finseq_2.html#D3">FINSEQ_2:def 3</a></i>;<br/><a NAME="E5:15_1_1_1"/><i><font color="Green">E12</font></i>: 
( <font color="Maroon">c<sub>5</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Maroon">c<sub>6</sub></font> iff <font color="Maroon">P<sub>1</sub></font>[<font color="Maroon">c<sub>5</sub></font>,<font color="Maroon">c<sub>6</sub></font>] )
 <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>7</sub></font> = <font color="Maroon">c<sub>3</sub></font> as   <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>2</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="txt" href="dtconstr.html#E1:15_1_1_1"><i><font color="Green">E10</font></i></a>, <a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>8</sub></font> = <font color="Maroon">c<sub>4</sub></font> as    <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1_1_1"><i><font color="Green">E11</font></i></a>, <a class="ref" href="finseq_2.html#D3">FINSEQ_2:def 3</a></i>;<br/><a NAME="E8:15_1_1_1"/>
<font color="Maroon">c<sub>7</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Maroon">c<sub>8</sub></font>
 <b>by </b><i><a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="txt" href="dtconstr.html#E1:15_1_1_1"><i><font color="Green">E10</font></i></a>, <a class="txt" href="dtconstr.html#E5:15_1_1_1"><i><font color="Green">E12</font></i></a>, <a class="ref" href="lang1.html#D1">LANG1:def 1</a></i>;<br/><b>hence </b><a NAME="E9:15_1_1_1"/>
<span class="p1"><a href="tarski.html#K4">[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="tarski.html#K4">]</a></span> <a href="hidden.html#R2">in</a> the <a href="lang1.html#U1">Rules</a> of <font color="Maroon">c<sub>2</sub></font>
 <b>by </b><i><a class="ref" href="lang1.html#D1">LANG1:def 1</a></i>;<br/></div>
<b>end;</b></div><b>assume </b><a NAME="E2:15_1_1"/><i><font color="Green">E10</font></i>: 
<span class="p1"><a href="tarski.html#K4">[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="tarski.html#K4">]</a></span> <a href="hidden.html#R2">in</a> the <a href="lang1.html#U1">Rules</a> of <font color="Maroon">c<sub>2</sub></font>
 ;<br/><a NAME="E3:15_1_1"/><b>then </b><i><font color="Green">E11</font></i>: 
( <font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R2">in</a> the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> &amp; <font color="Maroon">c<sub>4</sub></font> <a href="hidden.html#R2">in</a> the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> <a href="finseq_2.html#K3">*</a>  )
 <b>by </b><i><a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>5</sub></font> = <font color="Maroon">c<sub>3</sub></font> as   <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>2</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E2:15_1_1"><i><font color="Green">E10</font></i></a>, <a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>6</sub></font> = <font color="Maroon">c<sub>4</sub></font> as    <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>2</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E3:15_1_1"><i><font color="Green">E11</font></i></a>, <a class="ref" href="finseq_2.html#D3">FINSEQ_2:def 3</a></i>;<br/><a NAME="E6:15_1_1"/><i><font color="Green">E12</font></i>: 
( <font color="Maroon">c<sub>5</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Maroon">c<sub>6</sub></font> iff <font color="Maroon">P<sub>1</sub></font>[<font color="Maroon">c<sub>5</sub></font>,<font color="Maroon">c<sub>6</sub></font>] )
 <b>by </b><i><a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>7</sub></font> = <font color="Maroon">c<sub>3</sub></font> as   <a href="lang1.html#NM1">Symbol</a> of <font color="Maroon">c<sub>1</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1_1"><i><font color="Green">E10</font></i></a>, <a class="ref" href="zfmisc_1.html#T106">ZFMISC_1:106</a></i>;<br/><b>reconsider </b><font color="Maroon">c<sub>8</sub></font> = <font color="Maroon">c<sub>4</sub></font> as    <a href="finseq_1.html#M2">FinSequence</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">c<sub>1</sub></font> <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="txt" href="dtconstr.html#E3:15_1_1"><i><font color="Green">E11</font></i></a>, <a class="ref" href="finseq_2.html#D3">FINSEQ_2:def 3</a></i>;<br/><a NAME="E9:15_1_1"/>
<font color="Maroon">c<sub>7</sub></font> <a href="lang1.html#R1">==&gt;</a> <font color="Maroon">c<sub>8</sub></font>
 <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1_1"><i><font color="Green">E10</font></i></a>, <a class="txt" href="dtconstr.html#E6:15_1_1"><i><font color="Green">E12</font></i></a>, <a class="ref" href="lang1.html#D1">LANG1:def 1</a></i>;<br/><b>hence </b><a NAME="E10:15_1_1"/>
<span class="p1"><a href="tarski.html#K4">[</a><span class="default"><font color="Maroon">c<sub>3</sub></font>,<font color="Maroon">c<sub>4</sub></font></span><a href="tarski.html#K4">]</a></span> <a href="hidden.html#R2">in</a> the <a href="lang1.html#U1">Rules</a> of <font color="Maroon">c<sub>1</sub></font>
 <b>by </b><i><a class="ref" href="lang1.html#D1">LANG1:def 1</a></i>;<br/></div><b>end;</b></div>
<b>hence </b><a NAME="E4:15_1"/>
<font color="Maroon">c<sub>1</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font>
 <b>by </b><i><a class="txt" href="dtconstr.html#E1:15_1"><i><font color="Green">E8</font></i></a>, <a class="txt" href="dtconstr.html#E2:15_1"><i><font color="Green">E9</font></i></a>, <a class="ref" href="relat_1.html#D2">RELAT_1:def 2</a></i>;<br/>


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