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A215918 Numbers n such that 6*n + {1, 5, 7}  are all primes. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified November 21 00:36 EST 2018. Contains 317427 sequences. (Running on oeis4.)