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%I #3 Mar 30 2012 18:52:32
%S 15,21,25,27,39,45,49,51,57,63,65,69,75,81,85,87,93,105,115,117,123,
%T 129,135,143,147,153,155,159,165,169,177,183,185,187,189,195,201,203,
%U 205,207,209,213,215,217,219,221,225,231,235,237,243,245,247,249,253,255
%N Odd composite numbers whose reversal is a different composite.
%e If odd composite 15 < 51 = composite, then 15=a(1). If odd composite 21 > 12 = composite, then 21=a(2). If odd composite 25 < 52 = composite, then 25=a(3), etc.
%Y Cf. A006567, A071904.
%K nonn,base
%O 1,1
%A _Juri-Stepan Gerasimov_, Feb 03 2009
%E Added missing numbers in the 201-299 range. _R. J. Mathar_, Feb 13 2009
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