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<div><span class="kw">theorem </span><a NAME="T73"><span class="comment"><font color="firebrick">:: TREES_3:73</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">T1</font>, <font color="Olive" title="b2">T2</font>, <font color="Olive" title="b3">W1</font>, <font color="Olive" title="b4">W2</font> being   <a href="trees_1.html#NM1" title="TREES_1:NM.1">Tree</a>  st  <a href="trees_3.html#K13" title="TREES_3:func.13">tree</a> (<font color="Olive" title="b1">T1</font>,<font color="Olive" title="b2">T2</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="trees_3.html#K13" title="TREES_3:func.13">tree</a> (<font color="Olive" title="b3">W1</font>,<font color="Olive" title="b4">W2</font>) holds <br/>( <font color="Olive" title="b1">T1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b3">W1</font> &amp; <font color="Olive" title="b2">T2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b4">W2</font> )</div></div>
