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<a NAME="E1:15_1_1"/>
 <a href="qc_lang1.html#K11">VERUM</a>  <a href="hidden.html#R2">in</a> <span class="p1">{<span class="default"> <font color="Olive">s</font> where <font color="Olive">s</font> is   <a href="qc_lang1.html#NM8">QC-formula</a> : (  <a href="qc_lang3.html#K6">Fixed</a> <font color="Olive">s</font> <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a>  &amp;  <a href="qc_lang3.html#K5">Free</a> <font color="Olive">s</font> <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a>  ) </span>}</span> 
 
<b>by </b><i><a class="ref" href="qc_lang3.html#T65">QC_LANG3:65</a>, <a class="ref" href="qc_lang3.html#T76">QC_LANG3:76</a></i>;<br/>
<b>hence </b><a NAME="E2:15_1_1"/>
not  <a href="cqc_lang.html#K7" target="_self">CQC-WFF</a>  is <a href="xboole_0.html#V1">empty</a>
 ;<br/>


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