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<b>let </b><font color="Maroon" title="c1">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> for <font color="Olive" title="b1">T1</font>, <font color="Olive" title="b2">T2</font> being  <a href="trees_2.html#NM4" title="TREES_2:NM.4">DecoratedTree</a> holds  <span class="p1">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="trees_4.html#K6" title="TREES_4:func.6">-tree</a> <font color="Olive" title="b1">T1</font>,<font color="Olive" title="b2">T2</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c1">x</font></span><br/><b>let </b><font color="Maroon" title="c2">T1</font>, <font color="Maroon" title="c3">T2</font> be   <a href="trees_2.html#NM4" title="TREES_2:NM.4">DecoratedTree</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> <span class="p1">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="trees_4.html#K6" title="TREES_4:func.6">-tree</a> <font color="Maroon" title="c2">T1</font>,<font color="Maroon" title="c3">T2</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c1">x</font></span><br/>





<a NAME="E1:7"/>
<font color="Maroon" title="c1">x</font> <a href="trees_4.html#K6" title="TREES_4:func.6">-tree</a> <font color="Maroon" title="c2">T1</font>,<font color="Maroon" title="c3">T2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c1">x</font> <a href="trees_4.html#K4" title="TREES_4:func.4">-tree</a> <span class="p1"><a href="finseq_1.html#K10" title="FINSEQ_1:func.10">&lt;*</a><span class="default"><font color="Maroon" title="c2">T1</font>,<font color="Maroon" title="c3">T2</font></span><a href="finseq_1.html#K10" title="FINSEQ_1:func.10">*&gt;</a></span>
 
<b>by </b><i><a class="ref" href="trees_4.html#D6" title="TREES_4:def.6">TREES_4:def 6</a></i>;<br/>
<b>hence </b><a NAME="E2:7"/>
<span class="p1">(<span class="default"><font color="Maroon" title="c1">x</font> <a href="trees_4.html#K6" title="TREES_4:func.6">-tree</a> <font color="Maroon" title="c2">T1</font>,<font color="Maroon" title="c3">T2</font></span>)</span> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c1">x</font>
 <b>by </b><i><a class="ref" href="trees_4.html#D4" title="TREES_4:def.4">TREES_4:def 4</a></i>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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