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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E30">Th21</font></span>: <a NAME="T21"><span class="comment"><font color="firebrick">:: LATTICE5:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</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>  holds   <a href="lattice5.html#K8" title="LATTICE5:func.8">ConsecutiveSet</a> (<font color="Olive" title="b1">A</font>,<a href="numbers.html#K5" title="NUMBERS:func.5">0</a>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">A</font></div></div>
