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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E29">Th25</font></span>: <a NAME="T25"><span class="comment"><font color="firebrick">:: SHEFFER1:25</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">L</font> being   non  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>   <a href="lattices.html#L3" title="LATTICES:struct.3">LattStr</a>  holds <br/> ( <font color="Olive" title="b1">L</font> is   <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a>  <a href="lattices.html#NM1" title="LATTICES:NM.1">Lattice</a> iff ( <font color="Olive" title="b1">L</font> is  <a href="sheffer1.html#V2" title="SHEFFER1:attr.2">lower-bounded'</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="sheffer1.html#V1" title="SHEFFER1:attr.1">upper-bounded'</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="lattices.html#V4" title="LATTICES:attr.4">join-commutative</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="lattices.html#V6" title="LATTICES:attr.6">meet-commutative</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="lattices.html#V11" title="LATTICES:attr.11">distributive</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="sheffer1.html#V3" title="SHEFFER1:attr.3">distributive'</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="sheffer1.html#V4" title="SHEFFER1:attr.4">complemented'</a>  ) )</div></div>
