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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E4">Th4</font></span>: <a NAME="T4"><span class="comment"><font color="firebrick">:: CALCUL_2:4</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">a</font>, <font color="Olive" title="b2">b1</font>, <font color="Olive" title="b3">b2</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a> holds <br/> ( <font color="Olive" title="b2">b1</font> <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a> <font color="Olive" title="b3">b2</font> iff  <a href="calcul_2.html#K2" title="CALCUL_2:func.2">seq</a> (<font color="Olive" title="b1">a</font>,<font color="Olive" title="b2">b1</font>) <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="calcul_2.html#K2" title="CALCUL_2:func.2">seq</a> (<font color="Olive" title="b1">a</font>,<font color="Olive" title="b3">b2</font>) )</div></div>
