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<div><span class="kw">theorem </span><a NAME="T1"><span class="comment"><font color="firebrick">:: GOBRD10:1</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">i1</font>, <font color="Olive" title="b2">i2</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a>  st <font color="Olive" title="b1">i1</font>,<font color="Olive" title="b2">i2</font> <a href="gobrd10.html#R1" title="GOBRD10:pred.1">are_adjacent</a>  holds <br/><font color="Olive" title="b1">i1</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1,<font color="Olive" title="b2">i2</font> <a href="nat_1.html#K1" title="NAT_1:func.1">+</a> 1 <a href="gobrd10.html#R1" title="GOBRD10:pred.1">are_adjacent</a>  ;<br/></div></div>
