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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E37">PFO</font></span>: <a NAME="T51"><span class="comment"><font color="firebrick">:: RVSUM_4:51</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">f</font> being   <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  <a href="afinsq_1.html#NM1" title="AFINSQ_1:NM.1">XFinSequence</a> holds   <a href="rvsum_4.html#K14" title="RVSUM_4:func.14">XProduct</a> <font color="Olive" title="b1">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1</div></div>
