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<b>deffunc </b><font color="Maroon">H<sub>1</sub></font>(  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">S1</font>) <b>-&gt; </b>   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a>  =  <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,$1</span>)</span>;<br/>
<b>consider </b><font color="Maroon" title="c4">f</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><b> such that </b><br/><a NAME="E2:45_1_1"/><i><font color="Green" title="E26">A1</font></i>: 
(  <a href="relat_1.html#K1" title="RELAT_1:func.1">dom</a> <font color="Maroon" title="c4">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c1">S1</font> &amp; ( for <font color="Olive" title="b1">s</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">S1</font> holds  <font color="Maroon" title="c4">f</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">s</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Olive" title="b1">s</font>) ) )
 <b>from </b><i><a class="ref" href="funct_1.html#S4" title="FUNCT_1:sch.4">FUNCT_1:sch 4</a>();<br/></i>
<b>reconsider </b><font color="Maroon" title="c5">f</font> = <font color="Maroon" title="c4">f</font> as    <a href="pboole.html#M1" title="PBOOLE:mode.1">ManySortedSet</a> of the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c1">S1</font> <b>by </b><i><a class="txt" href="osalg_2.html#E2:45_1_1"><i><font color="Green" title="E26">A1</font></i></a>, <a class="ref" href="pboole.html#D3" title="PBOOLE:def.3">PBOOLE:def 3</a></i>;<br/>
<a NAME="E4:45_1_1"/>
<font color="Maroon" title="c5">f</font> <a href="pboole.html#R2" title="PBOOLE:pred.2">c=</a> the <a href="msualg_1.html#U4" title="MSUALG_1:sel.4">Sorts</a> of <font color="Maroon" title="c2">OU0</font>
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="45_1_1_1"><b>proof </b></a><div class="add">

<b>let </b><font color="Maroon" title="c6">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <i><font color="Red">:: according to </font></i><a class="ref" href="pboole.html#D5" title="PBOOLE:def.5">PBOOLE:def 5</a><br/>

<b>assume </b><a NAME="E1:45_1_1_1"/>
<font color="Maroon" title="c6">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c1">S1</font>
 ;<br/>

<b>then reconsider </b><font color="Maroon" title="c7">s</font> = <font color="Maroon" title="c6">x</font> as   <a href="osalg_1.html#NM1" title="OSALG_1:NM.1">SortSymbol</a> of <font color="Maroon" title="c1">S1</font> ;<br/>
<a NAME="E3:45_1_1_1"/><i><font color="Green" title="E27">A2</font></i>: 
<font color="Maroon" title="c5">f</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c7">s</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c7">s</font></span>)</span>
 
<b>by </b><i><a class="txt" href="osalg_2.html#E2:45_1_1"><i><font color="Green" title="E26">A1</font></i></a></i>;<br/>
<b>reconsider </b><font color="Maroon" title="c8">u0</font> = the <a href="msualg_1.html#U4" title="MSUALG_1:sel.4">Sorts</a> of <font color="Maroon" title="c2">OU0</font> as   <a href="msualg_2.html#NM1" title="MSUALG_2:NM.1">MSSubset</a> of <font color="Maroon" title="c2">OU0</font> <b>by </b><i><a class="ref" href="pboole.html#D23" title="PBOOLE:def.23">PBOOLE:def 23</a></i>;<br/>
<a NAME="E5:45_1_1_1"/>
<font color="Maroon" title="c8">u0</font> is   <a href="osalg_1.html#NM4" title="OSALG_1:NM.4">OrderSortedSet</a> of <font color="Maroon" title="c1">S1</font>
 
<b>by </b><i><a class="ref" href="osalg_1.html#T17" title="OSALG_1:th.17">OSALG_1:17</a></i>;<br/>
<a NAME="E6:45_1_1_1"/><b>then </b><i><font color="Green" title="E28">A3</font></i>: 
<font color="Maroon" title="c8">u0</font> is    <a href="osalg_2.html#M2" title="OSALG_2:mode.2">OSSubset</a> of <font color="Maroon" title="c2">OU0</font>
 
<b>by </b><i><a class="ref" href="osalg_2.html#D2" target="_self" title="OSALG_2:def.2">Def2</a></i>;<br/>
<a NAME="E7:45_1_1_1"/>
<font color="Maroon" title="c8">u0</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="osalg_2.html#K5" title="OSALG_2:func.5">OSSubSort</a> <font color="Maroon" title="c3">A</font>
 
<b>by </b><i><a class="ref" href="osalg_2.html#T22" target="_self" title="OSALG_2:th.22">Th22</a></i>;<br/>
<a NAME="E8:45_1_1_1"/><b>then </b>
the <a href="msualg_1.html#U4" title="MSUALG_1:sel.4">Sorts</a> of <font color="Maroon" title="c2">OU0</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c7">s</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c7">s</font>
 
<b>by </b><i><a class="txt" href="osalg_2.html#E6:45_1_1_1"><i><font color="Green" title="E28">A3</font></i></a>, <a class="ref" href="osalg_2.html#D10" target="_self" title="OSALG_2:def.10">Def10</a></i>;<br/>
<b>hence </b><a NAME="E9:45_1_1_1"/>
<font color="Maroon" title="c5">f</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c6">x</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> the <a href="msualg_1.html#U4" title="MSUALG_1:sel.4">Sorts</a> of <font color="Maroon" title="c2">OU0</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c6">x</font>
 <b>by </b><i><a class="txt" href="osalg_2.html#E3:45_1_1_1"><i><font color="Green" title="E27">A2</font></i></a>, <a class="ref" href="setfam_1.html#T4" title="SETFAM_1:th.4">SETFAM_1:4</a></i>;<br/>


</div><b>end;</b></div>
<b>then reconsider </b><font color="Maroon" title="c6">f</font> = <font color="Maroon" title="c5">f</font> as   <a href="msualg_2.html#NM1" title="MSUALG_2:NM.1">MSSubset</a> of <font color="Maroon" title="c2">OU0</font> <b>by </b><i><a class="ref" href="pboole.html#D23" title="PBOOLE:def.23">PBOOLE:def 23</a></i>;<br/>
<b>take </b>
<font color="Maroon" title="c6">f</font>
;<br/>

<b>reconsider </b><font color="Maroon" title="c7">f1</font> = <font color="Maroon" title="c6">f</font> as   <a href="struct_0.html#NM8" title="STRUCT_0:NM.8">ManySortedSet</a> of <font color="Maroon" title="c1">S1</font> ;<br/>
<a NAME="E7:45_1_1"/>
for <font color="Olive" title="b1">s1</font>, <font color="Olive" title="b2">s2</font> being  <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">S1</font>  st <font color="Olive" title="b1">s1</font> <a href="orders_2.html#R3" title="ORDERS_2:pred.3">&lt;=</a> <font color="Olive" title="b2">s2</font> holds <br/><font color="Maroon" title="c7">f1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">s1</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c7">f1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b2">s2</font>
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="45_1_1_2"><b>proof </b></a><div class="add">

<b>let </b><font color="Maroon" title="c8">s1</font>, <font color="Maroon" title="c9">s2</font> be   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">S1</font>;<br/>

<b>assume </b><a NAME="E1:45_1_1_2"/><i><font color="Green" title="E27">A4</font></i>: 
<font color="Maroon" title="c8">s1</font> <a href="orders_2.html#R3" title="ORDERS_2:pred.3">&lt;=</a> <font color="Maroon" title="c9">s2</font>
 ;<br/>

<b>reconsider </b><font color="Maroon" title="c10">s3</font> = <font color="Maroon" title="c8">s1</font>, <font color="Maroon" title="c11">s4</font> = <font color="Maroon" title="c9">s2</font> as   <a href="osalg_1.html#NM1" title="OSALG_1:NM.1">SortSymbol</a> of <font color="Maroon" title="c1">S1</font> ;<br/>
<a NAME="E3:45_1_1_2"/>
 <a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c11">s4</font> <a href="setfam_1.html#R2" title="SETFAM_1:pred.2">is_coarser_than</a>  <a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c10">s3</font>
 
<b>by </b><i><a class="txt" href="osalg_2.html#E1:45_1_1_2"><i><font color="Green" title="E27">A4</font></i></a>, <a class="ref" href="osalg_2.html#T26" target="_self" title="OSALG_2:th.26">Th26</a></i>;<br/>
<a NAME="E4:45_1_1_2"/><b>then </b><i><font color="Green" title="E28">A5</font></i>: 
 <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c8">s1</font></span>)</span> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c9">s2</font></span>)</span>
 
<b>by </b><i><a class="ref" href="setfam_1.html#T19" title="SETFAM_1:th.19">SETFAM_1:19</a></i>;<br/>
<a NAME="E5:45_1_1_2"/>
<font color="Maroon" title="c7">f1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">s1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Maroon" title="c8">s1</font></span>)</span>
 
<b>by </b><i><a class="txt" href="osalg_2.html#E2:45_1_1"><i><font color="Green" title="E26">A1</font></i></a></i>;<br/>
<b>hence </b><a NAME="E6:45_1_1_2"/>
<font color="Maroon" title="c7">f1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c8">s1</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c7">f1</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c9">s2</font>
 <b>by </b><i><a class="txt" href="osalg_2.html#E2:45_1_1"><i><font color="Green" title="E26">A1</font></i></a>, <a class="txt" href="osalg_2.html#E4:45_1_1_2"><i><font color="Green" title="E28">A5</font></i></a></i>;<br/>


</div><b>end;</b></div>
<a NAME="E8:45_1_1"/><b>then </b>
<font color="Maroon" title="c6">f</font> is   <a href="osalg_1.html#NM4" title="OSALG_1:NM.4">OrderSortedSet</a> of <font color="Maroon" title="c1">S1</font>
 
<b>by </b><i><a class="ref" href="osalg_1.html#D18" title="OSALG_1:def.18">OSALG_1:def 18</a></i>;<br/>
<b>hence </b><a NAME="E9:45_1_1"/>
( <font color="Maroon" title="c6">f</font> is    <a href="osalg_2.html#M2" title="OSALG_2:mode.2">OSSubset</a> of <font color="Maroon" title="c2">OU0</font> &amp; ( for <font color="Olive" title="b1">s</font> being  <a href="osalg_1.html#NM1" title="OSALG_1:NM.1">SortSymbol</a> of <font color="Maroon" title="c1">S1</font> holds  <font color="Maroon" title="c6">f</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Olive" title="b1">s</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="setfam_1.html#K1" title="SETFAM_1:func.1">meet</a> <span class="p1">(<span class="default"><a href="osalg_2.html#K8" title="OSALG_2:func.8">OSSubSort</a> <font color="Maroon" title="c3">A</font>,<font color="Olive" title="b1">s</font></span>)</span> ) )
 <b>by </b><i><a class="txt" href="osalg_2.html#E2:45_1_1"><i><font color="Green" title="E26">A1</font></i></a>, <a class="ref" href="osalg_2.html#D2" target="_self" title="OSALG_2:def.2">Def2</a></i>;<br/>


</div>
