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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E24">Th20</font></span>: <a NAME="T20"><span class="comment"><font color="firebrick">:: GROUP_22:20</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">G</font> being   <a href="struct_0.html#V8" title="STRUCT_0:attr.8">finite</a>  <a href="group_1.html#NM1" title="GROUP_1:NM.1">Group</a><br/>  for <font color="Olive" title="b2">H1</font>, <font color="Olive" title="b3">H2</font> being   <a href="algstr_0.html#V15" title="ALGSTR_0:attr.15">strict</a>   <a href="group_2.html#M1" title="GROUP_2:mode.1">Subgroup</a> of <font color="Olive" title="b1">G</font>  st <font color="Olive" title="b2">H1</font>,<font color="Olive" title="b3">H2</font> <a href="group_6.html#R2" title="GROUP_6:pred.2">are_isomorphic</a>  holds <br/> <a href="group_2.html#K18" title="GROUP_2:func.18">index</a> <font color="Olive" title="b2">H1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="group_2.html#K18" title="GROUP_2:func.18">index</a> <font color="Olive" title="b3">H2</font></div></div>
