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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th19</font></span>: <a NAME="T19"><span class="comment"><font color="firebrick">:: NAT_6:19</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">n</font> being   <a href="ordinal1.html#V7" title="ORDINAL1:attr.7">natural</a>   <a href="ordinal1.html#NM2" title="ORDINAL1:NM.2">number</a>  holds <br/> (  <a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1,1 <a href="int_1.html#R2" title="INT_1:pred.2">are_congruent_mod</a> <font color="Olive" title="b1">n</font> iff ( <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 2 or <font color="Olive" title="b1">n</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 ) )</div></div>
