<?xml version="1.0"?>
<div><span class="kw">theorem </span><a NAME="T62"><span class="comment"><font color="firebrick">:: GROUP_23:62</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">I</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a> <br/>  for <font color="Olive" title="b2">F</font>, <font color="Olive" title="b3">Z</font> being   <a href="group_19.html#NM1" title="GROUP_19:NM.1">Group-Family</a> of <font color="Olive" title="b1">I</font>  st (  for <font color="Olive" title="b4">i</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">I</font> holds  <font color="Olive" title="b3">Z</font> <a href="group_7.html#K1" title="GROUP_7:func.1">.</a> <font color="Olive" title="b4">i</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="group_5.html#K10" title="GROUP_5:func.10">center</a> <span class="p1">(<span class="default"><font color="Olive" title="b2">F</font> <a href="group_7.html#K1" title="GROUP_7:func.1">.</a> <font color="Olive" title="b4">i</font></span>)</span> ) holds <br/> <a href="group_5.html#K10" title="GROUP_5:func.10">center</a> <span class="p1">(<span class="default"><a href="group_7.html#K2" title="GROUP_7:func.2">product</a> <font color="Olive" title="b2">F</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="group_7.html#K2" title="GROUP_7:func.2">product</a> <font color="Olive" title="b3">Z</font></div></div>
