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<div><span class="kw">theorem </span><a NAME="T67"><span class="comment"><font color="firebrick">:: TREES_3:67</font></span><br/></a><div class="add"> <a href="trees_3.html#K12" title="TREES_3:func.12">^</a> <span class="p1">(<span class="default"><a href="trees_1.html#K2" title="TREES_1:func.2">elementary_tree</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="trees_1.html#K2" title="TREES_1:func.2">elementary_tree</a> 1</div></div>
