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<div><span class="kw">theorem </span><a NAME="T64"><span class="comment"><font color="firebrick">:: ORDINAL5:64</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font> being   <a href="ordinal5.html#V6" title="ORDINAL5:attr.6">Cantor-normal-form</a>  <a href="ordinal2.html#NM1" title="ORDINAL2:NM.1">Ordinal-Sequence</a>  st  <a href="ordinal5.html#K4" title="ORDINAL5:func.4">Sum^</a> <font color="Olive" title="b1">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  holds <br/><font color="Olive" title="b1">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> </div></div>
