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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E12">Th15</font></span>: <a NAME="T15"><span class="comment"><font color="firebrick">:: EXCHSORT:15</font></span><br/></a><div class="add">(  <a href="exchsort.html#K1" title="EXCHSORT:func.1">base-</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  &amp;  <a href="exchsort.html#K2" title="EXCHSORT:func.2">limit-</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  &amp;  <a href="exchsort.html#K3" title="EXCHSORT:func.3">len-</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  )</div></div>
