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<div><span class="kw">theorem </span><a NAME="T19"><span class="comment"><font color="firebrick">:: HEYTING3:19</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">n</font>, <font color="Olive" title="b2">m</font>, <font color="Olive" title="b3">k</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of  <a href="numbers.html#NK1" title="NUMBERS:NK.1">NAT</a>   st <font color="Olive" title="b1">n</font> <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a> <font color="Olive" title="b3">k</font> holds <br/> <a href="heyting3.html#K3" title="HEYTING3:func.3">PFCrt</a> (<font color="Olive" title="b1">n</font>,<font color="Olive" title="b2">m</font>) <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="heyting3.html#K3" title="HEYTING3:func.3">PFCrt</a> (<font color="Olive" title="b3">k</font>,<font color="Olive" title="b2">m</font>)</div></div>
