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<div><span class="kw">theorem </span><a NAME="T21"><span class="comment"><font color="firebrick">:: CARD_5:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">a</font> being   <a href="card_5.html#NM1" title="CARD_5:NM.1">Aleph</a> holds   <a href="tarski.html#K3" title="TARSKI:func.3">union</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">a</font> <span class="kw">by</span> <span class="lab"><a class="ref" href="ordinal1.html#D6" onmouseover="rs('ordinal1/D6')" onmouseout="rh()">ORDINAL1:def 6</a></span>;<br/></div></div>
