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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E30">Th20</font></span>: <a NAME="T20"><span class="comment"><font color="firebrick">:: PRVECT_1:20</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">a</font> being   <a href="prvect_1.html#NM1" title="PRVECT_1:NM.1">Domain-Sequence</a><br/>  for <font color="Olive" title="b2">b</font> being    <a href="prvect_1.html#M1" title="PRVECT_1:mode.1">BinOps</a> of <font color="Olive" title="b1">a</font><br/>  for <font color="Olive" title="b3">u</font> being    <a href="prvect_1.html#M2" title="PRVECT_1:mode.2">UnOps</a> of <font color="Olive" title="b1">a</font>  st (  for <font color="Olive" title="b4">i</font> being    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="finseq_1.html#K4" title="FINSEQ_1:func.4">dom</a> <font color="Olive" title="b1">a</font> holds <br/> ( <font color="Olive" title="b3">u</font> <a href="prvect_1.html#K10" title="PRVECT_1:func.10">.</a> <font color="Olive" title="b4">i</font> <a href="finseqop.html#R1" title="FINSEQOP:pred.1">is_an_inverseOp_wrt</a> <font color="Olive" title="b2">b</font> <a href="prvect_1.html#K9" title="PRVECT_1:func.9">.</a> <font color="Olive" title="b4">i</font> &amp; <font color="Olive" title="b2">b</font> <a href="prvect_1.html#K9" title="PRVECT_1:func.9">.</a> <font color="Olive" title="b4">i</font> is  <a href="setwiseo.html#V1" title="SETWISEO:attr.1">having_a_unity</a>  ) ) holds <br/> <a href="prvect_1.html#K11" title="PRVECT_1:func.11">Frege</a> <font color="Olive" title="b3">u</font> <a href="finseqop.html#R1" title="FINSEQOP:pred.1">is_an_inverseOp_wrt</a> <span class="p1"><a href="prvect_1.html#K12" title="PRVECT_1:func.12">[:</a><span class="default"><font color="Olive" title="b2">b</font></span><a href="prvect_1.html#K12" title="PRVECT_1:func.12">:]</a></span></div></div>
