A215918 Numbers n such that 6*n + {1, 5, 7} are all primes.

1, 2, 6, 11, 16, 17, 32, 37, 46, 51, 76, 102, 137, 142, 146, 181, 216, 237, 241, 247, 277, 282, 297, 311, 312, 332, 347, 356, 396, 447, 451, 466, 527, 542, 576, 577, 641, 692, 752, 797, 871, 902, 906, 941, 942, 956, 1091, 1137, 1201, 1292, 1312, 1381, 1437

Offset

1,2

Comments

Subsequence of A056956.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Formula

a(n) = (A022005(n)-1)/6.

Mathematica

Select[Range[1437], Union[PrimeQ[6 # + {1, 5, 7}]] == {True} &] (* T. D. Noe, Aug 27 2012 *)

Prog

(PARI) for(n=1, 2000, if(isprime(6*n+1)&&isprime(6*n+5)&&isprime(6*n+7), print(n", ")))
(Magma) [n: n in [1..1000] | forall{6*n+r: r in [1, 5, 7] | IsPrime(6*n+r)}]; // Bruno Berselli, Aug 27 2012

Crossrefs

Cf. A022005, A056956.

Sequence in context: A190889 A020966 A193910 * A078476 A217687 A212459

Adjacent sequences: A215915 A215916 A215917 * A215919 A215920 A215921

Keyword

nonn,easy

Author

Zak Seidov, Aug 27 2012

Status

approved