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<a NAME="E1:12_2_1"/>
not the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">R</font> <a href="xboole_0.html#K2">\/</a> the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">S</font> is <a href="xboole_0.html#V1">empty</a>
 
;<br/>
<a NAME="E2:12_2_1"/><b>then </b>
not the <a href="struct_0.html#U1">carrier</a> of <span class="p1">(<span class="default"><a href="neckla_2.html#K2">sum_of</a> <font color="Maroon">R</font>,<font color="Maroon">S</font></span>)</span> is <a href="xboole_0.html#V1">empty</a>
 
<b>by </b><i><a class="ref" href="neckla_2.html#D3">NECKLA_2:def 3</a></i>;<br/>
<b>hence </b><a NAME="E3:12_2_1"/>
not  <a href="neckla_2.html#K2">sum_of</a> <font color="Maroon">R</font>,<font color="Maroon">S</font> is <a href="struct_0.html#V3">empty</a>
 <b>by </b><i><a class="ref" href="struct_0.html#D1">STRUCT_0:def 1</a></i>;<br/>


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