A024902 Numbers k such that 7*k + 4 is prime.

1, 7, 9, 15, 19, 21, 25, 27, 37, 39, 49, 55, 61, 69, 79, 81, 85, 87, 91, 97, 105, 115, 117, 129, 139, 141, 145, 147, 151, 157, 159, 169, 171, 175, 189, 205, 207, 211, 217, 225, 229, 231, 237, 247, 249, 255, 261, 267, 271, 285, 289, 295, 297, 301, 307, 319, 321, 327, 339, 349

Offset

1,2

Links

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

Mathematica

Select[Range[400], PrimeQ[7 # + 4] &] (* Vincenzo Librandi, Sep 26 2012 *)

Prog

(Magma) [n: n in [1..400] | IsPrime(7*n+4)]; // Vincenzo Librandi, Nov 20 2010
(PARI) is(n)=isprime(7*n+4) \\ Charles R Greathouse IV, Feb 20 2017

Crossrefs

Cf. A045471 (associated primes).

Sequence in context: A347436 A047522 A112072 * A111312 A357500 A158891

Adjacent sequences: A024899 A024900 A024901 * A024903 A024904 A024905

Keyword

nonn,easy

Author

Clark Kimberling

Status

approved