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%I #13 Sep 08 2022 08:46:03
%S 1,2,6,11,16,17,32,37,46,51,76,102,137,142,146,181,216,237,241,247,
%T 277,282,297,311,312,332,347,356,396,447,451,466,527,542,576,577,641,
%U 692,752,797,871,902,906,941,942,956,1091,1137,1201,1292,1312,1381,1437
%N Numbers n such that 6*n + {1, 5, 7} are all primes.
%C Subsequence of A056956.
%H Vincenzo Librandi, <a href="/A215918/b215918.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = (A022005(n)-1)/6.
%t Select[Range[1437], Union[PrimeQ[6 # + {1, 5, 7}]] == {True} &] (* _T. D. Noe_, Aug 27 2012 *)
%o (PARI) for(n=1,2000,if(isprime(6*n+1)&&isprime(6*n+5)&&isprime(6*n+7),print(n",")))
%o (Magma) [n: n in [1..1000] | forall{6*n+r: r in [1,5,7] | IsPrime(6*n+r)}]; // _Bruno Berselli_, Aug 27 2012
%Y Cf. A022005, A056956.
%K nonn,easy
%O 1,2
%A _Zak Seidov_, Aug 27 2012