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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E22">Th20</font></span>: <a NAME="T20"><span class="comment"><font color="firebrick">:: NAT_3:20</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font> being    <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>  holds   <a href="nat_3.html#K8" title="NAT_3:func.8">Product</a> <span class="p1">(<span class="default"><a href="pre_poly.html#K16" title="PRE_POLY:func.16">EmptyBag</a> <font color="Olive" title="b1">A</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1</div></div>
