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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th21</font></span>: <a NAME="T22"><span class="comment"><font color="firebrick">:: TREES_1:22</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">T</font> being   <a href="trees_1.html#NM1" title="TREES_1:NM.1">Tree</a> holds <br/> (  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Olive" title="b1">T</font> &amp;  <a href="finseq_1.html#K6" title="FINSEQ_1:func.6">&lt;*&gt;</a> <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Olive" title="b1">T</font> )</div></div>
