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%I #4 Mar 31 2012 21:03:15
%S 7,13,37,61,103,113,149,151,181,197,199,251,263,269,271,421,439,479,
%T 487,523,631,643,653,661,677,769,811,829,853,937,947,1019,1039,1049,
%U 1051,1277,1319,1399,1427,1489,1543,1663,1753,1759,1831,1867,1901,1933,1949,1999,2039
%N Primes p = prime(c) with index c a composite such that the concatenation c//p is a prime.
%e The composite c=4 of A002808 addresses prime(4) = 7 and the concatenation 47 is a prime, which adds 7 to the sequence.
%e The composite c=6 addresses prime(6)=13 and the concatenation 613 is prime which adds 13 to the sequence.
%Y Cf. A000027, A000040, A002808.
%K nonn,base,less
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 19 2009
%E Edited and extended beyond 61 by _R. J. Mathar_, May 05 2010