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<div><span class="kw">theorem </span><a NAME="T80"><span class="comment"><font color="firebrick">:: SURREALN:80</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font> being   <a href="ordinal1.html#NM3" title="ORDINAL1:NM.3">Ordinal</a>  ex <font color="Olive" title="b2">x</font> being   <a href="surrealn.html#V3" title="SURREALN:attr.3">No_ordinal</a>  <a href="surreal0.html#NM1" title="SURREAL0:NM.1">Surreal</a> st <br/>(  <a href="surreal0.html#K12" title="SURREAL0:func.12">born</a> <font color="Olive" title="b2">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">A</font> &amp;  <a href="surrealn.html#K9" title="SURREALN:func.9">No_uOrdinal_op</a> <font color="Olive" title="b1">A</font> <a href="surrealo.html#R2" title="SURREALO:pred.2">==</a> <font color="Olive" title="b2">x</font> &amp; (  for <font color="Olive" title="b3">o</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>  holds <br/> ( <font color="Olive" title="b3">o</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="surreal0.html#K1" title="SURREAL0:func.1">L_</a> <font color="Olive" title="b2">x</font> iff  ex <font color="Olive" title="b4">B</font> being   <a href="ordinal1.html#NM3" title="ORDINAL1:NM.3">Ordinal</a> st <br/>( <font color="Olive" title="b4">B</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Olive" title="b1">A</font> &amp; <font color="Olive" title="b3">o</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="surrealn.html#K9" title="SURREALN:func.9">No_uOrdinal_op</a> <font color="Olive" title="b4">B</font> ) ) ) )</div></div>
