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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E4">Th3</font></span>: <a NAME="T3"><span class="comment"><font color="firebrick">:: DTCONSTR:3</font></span><br/></a><div class="add"> <a href="trees_3.html#K15" title="TREES_3:func.15">roots</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <span class="kw">by</span> <span class="lab"><a class="txt" href="dtconstr.html#E3"><span class="lab"><font color="Green" title="E3">Lm1</font></span></a></span>;<br/></div></div>
