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%I #4 Dec 05 2013 19:56:16
%S 3,1,1,39,87,57,171,129,219,399,459,1719,719,61,5811,383,1519,23889,
%T 1001,3133,4491,4767,519,4253,111,34251,12303,5143,16943,19293,361,
%U 21771,18803,2919,44787,66819,42897,21541,15299,21387,11613,29133,16839
%N a(1) = 3; a(n) = smallest number such that the forward as well as the reverse n-th partial concatenation is a prime for n>1. (Reverse concatenation is taken term-wise and not digit-wise).
%Y Cf. A083992, A083994.
%K base,nonn
%O 0,1
%A _Amarnath Murthy_, May 23 2003
%E Corrected and extended by _Ray Chandler_, Aug 03 2003