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%I #11 Jul 14 2015 01:12:36
%S 13,79,911,2729,3739,4547,4951,5153,5557,6163,6971,7577,105107,109111,
%T 115117,117119,121123,151153,159161,181183,187189,195197,201203,
%U 211213,217219,225227,247249,271273,277279,285287,289291
%N Primes that are concatenations of n with n + 2.
%C Or, primes which are the concatenation of two consecutive odd numbers. - _Parthasarathy Nambi_, Apr 11 2005
%e The first term is 13 which is a prime and is the concatenation of 1 and 3 - the first two odd numbers.
%t lp = Range[1, 320, 2]; lst = {}; Do[p = FromDigits[ Join[ IntegerDigits[ lp[[n]]], IntegerDigits[ lp[[n + 1]] ]]]; If[ PrimeQ[p], AppendTo[lst, p]], {n, 159}]; lst (* _Robert G. Wilson v_, Apr 12 2005 *)
%Y Cf. A032607, A032617.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, May 15 1998
%E Edited by _N. J. A. Sloane_, May 21 2008 at the suggestion of _R. J. Mathar_