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A232238 Primes p such that p+2 and q are primes, where q is concatenation of binary representations of p and p+2: q = p * 2^L + p+2, where L is the length of binary representation of p+2: L=A070939(p+2).

%I A232238 #6 Nov 21 2013 15:23:31
%S A232238 3,5,17,71,269,1049,1151,1721,5099,5279,5657,6299,6569,6779,7307,7589,
%T A232238 16451,16649,16691,19079,19139,19211,19841,19961,20771,20981,21011,
%U A232238 21059,21599,22619,22961,23201,23369,23741,23909,24419,26729,26951,27689,28109,28409,28751,29129
%N A232238 Primes p such that p+2 and q are primes, where q is concatenation of binary representations of p and p+2: q = p * 2^L + p+2, where L is the length of binary representation of p+2: L=A070939(p+2).
%F A232238 A232236(n) = a(n) * 2^A070939(a(n)+2) + a(n)+2.
%e A232238 3 is 11 in binary, 5 is 101. Because 11101 = 29d is a prime, 3 is in the sequence.
%e A232238 5 is 101 in binary, 7 is 111, and because 101111 = 47d is a prime, 5 is in the sequence.
%Y A232238 Cf. A000040, A070939, A232236.
%K A232238 nonn,base,less
%O A232238 1,1
%A A232238 _Alex Ratushnyak_, Nov 20 2013