<?xml version="1.0"?>
<div class="add">

<span class="kw">let </span><font color="Maroon" title="c2">e</font> be    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">X</font>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c2">e</font> is  <a href="finseq_1.html#V1" title="FINSEQ_1:attr.1">FinSequence-like</a> </span><br/>

<a NAME="E1:168_1_1"/>
( <font color="Maroon" title="c1">X</font> is  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  or  not <font color="Maroon" title="c1">X</font> is  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  )
 
;<br/>
<a NAME="E2:168_1_1"/><span class="kw">then </span>
( <font color="Maroon" title="c2">e</font> is  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  or <font color="Maroon" title="c2">e</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c1">X</font> )
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="subset_1.html#D2" title="SUBSET_1:def.2">SUBSET_1:def 2</a></span>;<br/>
<span class="kw">hence </span><a NAME="E3:168_1_1"/>
<font color="Maroon" title="c2">e</font> is  <a href="finseq_1.html#V1" title="FINSEQ_1:attr.1">FinSequence-like</a> 
 <span class="kw">by</span> <span class="lab"><a class="ref" href="finseq_1.html#D19" target="_self" title="FINSEQ_1:def.19">Def19</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="Red">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div>
