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<span class="kw">let </span><font color="Maroon" title="c1">K</font>, <font color="Maroon" title="c2">L</font>, <font color="Maroon" title="c3">M</font>, <font color="Maroon" title="c4">N</font> be   <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c1">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> &amp; <font color="Maroon" title="c3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">N</font> implies ( <font color="Maroon" title="c1">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c4">N</font> &amp; <font color="Maroon" title="c3">M</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c1">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c4">N</font> ) )</span><br/>







<a NAME="E1:99"/><span class="lab"><font color="Green" title="E64">A1</font></span>: 
 for <font color="Olive" title="b1">K</font>, <font color="Olive" title="b2">L</font>, <font color="Olive" title="b3">M</font>, <font color="Olive" title="b4">N</font> being   <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a>  st <font color="Olive" title="b1">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Olive" title="b2">L</font> &amp; <font color="Olive" title="b3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Olive" title="b4">N</font> &amp; <font color="Olive" title="b2">L</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Olive" title="b4">N</font> holds <br/><font color="Olive" title="b1">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Olive" title="b3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Olive" title="b2">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Olive" title="b4">N</font>
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="99_1"><span class="kw">proof </span></a><div class="add">

<span class="kw">let </span><font color="Maroon" title="c5">K</font>, <font color="Maroon" title="c6">L</font>, <font color="Maroon" title="c7">M</font>, <font color="Maroon" title="c8">N</font> be   <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c5">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> &amp; <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c8">N</font> &amp; <font color="Maroon" title="c6">L</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c8">N</font> implies <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font> )</span><br/>







<span class="kw">assume </span><span class="kw">that </span><br/><a NAME="E1:99_1"/><span class="lab"><font color="Green" title="E65">A2</font></span>: 
<font color="Maroon" title="c5">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font>
 <span class="kw">and </span><br/><a NAME="E2:99_1"/><span class="lab"><font color="Green" title="E66">A3</font></span>: 
<font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">and </span><br/><a NAME="E3:99_1"/><span class="lab"><font color="Green" title="E67">A4</font></span>: 
<font color="Maroon" title="c6">L</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c8">N</font>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font></span><br/>

<div><span class="lab"><font color="Green" title="E68">A5</font></span>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="99_1_1"><span class="kw">now </span></a><div class="add"><span class="kw">assume </span><a NAME="E1:99_1_1"/><span class="lab"><font color="Green" title="E69">A6</font></span>: 
<font color="Maroon" title="c8">N</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> 
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font></span><br/><span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c9">N</font> = <font color="Maroon" title="c8">N</font> as   <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a> ;<br/><span class="kw">reconsider </span><font color="Maroon" title="c10">L</font> = <font color="Maroon" title="c6">L</font>, <font color="Maroon" title="c11">M</font> = <font color="Maroon" title="c7">M</font>, <font color="Maroon" title="c12">K</font> = <font color="Maroon" title="c5">K</font> as   <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99_1"><span class="lab"><font color="Green" title="E65">A2</font></span></a>, <a class="txt" href="#E2:99_1"><span class="lab"><font color="Green" title="E66">A3</font></span></a>, <a class="txt" href="#E3:99_1"><span class="lab"><font color="Green" title="E67">A4</font></span></a>, <a class="txt" href="#E1:99_1_1"><span class="lab"><font color="Green" title="E69">A6</font></span></a>, <a class="ref" href="card_3.html#T92" title="CARD_3:th.92">CARD_3:92</a></span>;<br/><a NAME="E4:99_1_1"/><span class="lab"><font color="Green" title="E70">A7</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c12">K</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c12">K</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><a NAME="E5:99_1_1"/><span class="lab"><font color="Green" title="E71">A8</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">L</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c10">L</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><a NAME="E6:99_1_1"/><span class="lab"><font color="Green" title="E72">A9</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c11">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c11">M</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><a NAME="E7:99_1_1"/><span class="lab"><font color="Green" title="E73">A10</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">N</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c9">N</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><a NAME="E8:99_1_1"/><span class="lab"><font color="Green" title="E74">A11</font></span>: 
<font color="Maroon" title="c12">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c11">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c12">K</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c11">M</font></span>)</span></span>)</span>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:99_1_1"><span class="lab"><font color="Green" title="E70">A7</font></span></a>, <a class="txt" href="#E6:99_1_1"><span class="lab"><font color="Green" title="E72">A9</font></span></a>, <a class="ref" href="card_2.html#T38" target="_self" title="CARD_2:th.38">Th51</a></span>;<br/><a NAME="E9:99_1_1"/><span class="lab"><font color="Green" title="E75">A12</font></span>: 
<font color="Maroon" title="c10">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c9">N</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">L</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">N</font></span>)</span></span>)</span>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E5:99_1_1"><span class="lab"><font color="Green" title="E71">A8</font></span></a>, <a class="txt" href="#E7:99_1_1"><span class="lab"><font color="Green" title="E73">A10</font></span></a>, <a class="ref" href="card_2.html#T38" target="_self" title="CARD_2:th.38">Th51</a></span>;<br/><a NAME="E10:99_1_1"/><span class="lab"><font color="Green" title="E76">A13</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c12">K</font> <a href="xxreal_0.html#NR3" title="XXREAL_0:NR.3">&lt;</a>  <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">L</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99_1"><span class="lab"><font color="Green" title="E65">A2</font></span></a>, <a class="txt" href="#E4:99_1_1"><span class="lab"><font color="Green" title="E70">A7</font></span></a>, <a class="txt" href="#E5:99_1_1"><span class="lab"><font color="Green" title="E71">A8</font></span></a>, <a class="ref" href="nat_1.html#T41" title="NAT_1:th.41">NAT_1:41</a></span>;<br/><a NAME="E11:99_1_1"/>
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c11">M</font> <a href="xxreal_0.html#NR3" title="XXREAL_0:NR.3">&lt;</a>  <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:99_1"><span class="lab"><font color="Green" title="E66">A3</font></span></a>, <a class="txt" href="#E6:99_1_1"><span class="lab"><font color="Green" title="E72">A9</font></span></a>, <a class="txt" href="#E7:99_1_1"><span class="lab"><font color="Green" title="E73">A10</font></span></a>, <a class="ref" href="nat_1.html#T41" title="NAT_1:th.41">NAT_1:41</a></span>;<br/><a NAME="E12:99_1_1"/><span class="kw">then </span>
<span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c12">K</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c11">M</font></span>)</span> <a href="xxreal_0.html#NR3" title="XXREAL_0:NR.3">&lt;</a> <span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">L</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">N</font></span>)</span>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E10:99_1_1"><span class="lab"><font color="Green" title="E76">A13</font></span></a>, <a class="ref" href="xreal_1.html#T8" title="XREAL_1:th.8">XREAL_1:8</a></span>;<br/><span class="kw">hence </span><a NAME="E13:99_1_1"/>
<font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E8:99_1_1"><span class="lab"><font color="Green" title="E74">A11</font></span></a>, <a class="txt" href="#E9:99_1_1"><span class="lab"><font color="Green" title="E75">A12</font></span></a>, <a class="ref" href="nat_1.html#T41" title="NAT_1:th.41">NAT_1:41</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div>
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="99_1_2"><span class="kw">now </span></a><div class="add"><span class="kw">assume </span><a NAME="E1:99_1_2"/><span class="lab"><font color="Green" title="E69">A14</font></span>: 
 not <font color="Maroon" title="c8">N</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> 
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font></span><br/><a NAME="E2:99_1_2"/><span class="kw">then </span><span class="lab"><font color="Green" title="E70">A15</font></span>: 
<font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:99_1"><span class="lab"><font color="Green" title="E67">A4</font></span></a>, <a class="ref" href="card_2.html#T76" target="_self" title="CARD_2:th.76">Th118</a></span>;<br/><a NAME="E3:99_1_2"/><span class="lab"><font color="Green" title="E71">A16</font></span>: 
 <a href="ordinal1.html#K4" title="ORDINAL1:func.4">omega</a>  <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99_1_2"><span class="lab"><font color="Green" title="E69">A14</font></span></a>, <a class="ref" href="card_3.html#T85" title="CARD_3:th.85">CARD_3:85</a></span>;<br/><a NAME="E4:99_1_2"/>
( ( <font color="Maroon" title="c5">K</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c7">M</font> &amp; ( <font color="Maroon" title="c7">M</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  or  not <font color="Maroon" title="c7">M</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  ) ) or ( <font color="Maroon" title="c7">M</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c5">K</font> &amp; ( <font color="Maroon" title="c5">K</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  or  not <font color="Maroon" title="c5">K</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  ) ) )
 ;<br/><a NAME="E5:99_1_2"/><span class="kw">then </span><span class="lab"><font color="Green" title="E72">A17</font></span>: 
( ( <font color="Maroon" title="c5">K</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  &amp; <font color="Maroon" title="c7">M</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  ) or <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c7">M</font> or ( <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">K</font> &amp; <font color="Maroon" title="c5">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c8">N</font> ) )
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99_1"><span class="lab"><font color="Green" title="E65">A2</font></span></a>, <a class="txt" href="#E3:99_1"><span class="lab"><font color="Green" title="E67">A4</font></span></a>, <a class="ref" href="card_2.html#T76" target="_self" title="CARD_2:th.76">Th118</a></span>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="99_1_2_1"><span class="kw">now </span></a><div class="add"><span class="kw">assume </span><span class="kw">that </span><br/><a NAME="E1:99_1_2_1"/><span class="lab"><font color="Green" title="E73">A18</font></span>: 
<font color="Maroon" title="c5">K</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> 
 <span class="kw">and </span><br/><a NAME="E2:99_1_2_1"/><span class="lab"><font color="Green" title="E74">A19</font></span>: 
<font color="Maroon" title="c7">M</font> is  <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> 
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font></span><br/><span class="kw">reconsider </span><font color="Maroon" title="c9">K</font> = <font color="Maroon" title="c5">K</font>, <font color="Maroon" title="c10">M</font> = <font color="Maroon" title="c7">M</font> as   <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>  <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a> <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99_1_2_1"><span class="lab"><font color="Green" title="E73">A18</font></span></a>, <a class="txt" href="#E2:99_1_2_1"><span class="lab"><font color="Green" title="E74">A19</font></span></a></span>;<br/><a NAME="E4:99_1_2_1"/><span class="lab"><font color="Green" title="E75">A20</font></span>: 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">K</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c9">K</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><a NAME="E5:99_1_2_1"/>
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c10">M</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>;<br/><span class="kw">then </span><font color="Maroon" title="c9">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c10">M</font> = 
 <a href="card_1.html#K5" title="CARD_1:func.5">card</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">K</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p2">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">M</font></span>)</span></span>)</span>
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:99_1_2_1"><span class="lab"><font color="Green" title="E75">A20</font></span></a>, <a class="ref" href="card_2.html#T38" target="_self" title="CARD_2:th.38">Th51</a></span>
<br/>.= 
<span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c9">K</font></span>)</span> <a href="nat_1.html#K2" title="NAT_1:func.2">+</a> <span class="p1">(<span class="default"><a href="card_1.html#K5" title="CARD_1:func.5">card</a> <font color="Maroon" title="c10">M</font></span>)</span>
<span class="kw">by</span> <span class="lab"><a class="ref" href="card_1.html#D2" title="CARD_1:def.2">CARD_1:def 2</a></span>
;<br/><span class="kw">hence </span><a NAME="E7:99_1_2_1"/>
<font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:99_1_2"><span class="lab"><font color="Green" title="E70">A15</font></span></a>, <a class="txt" href="#E3:99_1_2"><span class="lab"><font color="Green" title="E71">A16</font></span></a>, <a class="ref" href="tarski.html#D3" title="TARSKI:def.3">TARSKI:def 3</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div><span class="kw">hence </span><a NAME="E7:99_1_2"/>
<font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E2:99_1"><span class="lab"><font color="Green" title="E66">A3</font></span></a>, <a class="txt" href="#E3:99_1"><span class="lab"><font color="Green" title="E67">A4</font></span></a>, <a class="txt" href="#E1:99_1_2"><span class="lab"><font color="Green" title="E69">A14</font></span></a>, <a class="txt" href="#E5:99_1_2"><span class="lab"><font color="Green" title="E72">A17</font></span></a>, <a class="ref" href="card_2.html#T76" target="_self" title="CARD_2:th.76">Th118</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div>
<span class="kw">hence </span><a NAME="E6:99_1"/>
<font color="Maroon" title="c5">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c7">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c6">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c8">N</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E4:99_1"><span class="lab"><font color="Green" title="E68">A5</font></span></a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>
<a NAME="E2:99"/>
( <font color="Maroon" title="c2">L</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c4">N</font> or <font color="Maroon" title="c4">N</font> <a href="ordinal1.html#R1" title="ORDINAL1:pred.1">c=</a> <font color="Maroon" title="c2">L</font> )
 
;<br/>
<span class="kw">hence </span><a NAME="E3:99"/>
( <font color="Maroon" title="c1">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> &amp; <font color="Maroon" title="c3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c4">N</font> implies ( <font color="Maroon" title="c1">K</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c3">M</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c4">N</font> &amp; <font color="Maroon" title="c3">M</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c1">K</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c2">L</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c4">N</font> ) )
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E1:99"><span class="lab"><font color="Green" title="E64">A1</font></span></a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div>
