A023222 Primes p such that 6*p + 7 is also prime.

2, 5, 11, 17, 29, 31, 37, 61, 67, 71, 89, 101, 109, 127, 137, 167, 181, 191, 199, 229, 241, 257, 269, 277, 281, 311, 331, 337, 347, 359, 379, 389, 397, 419, 431, 457, 491, 499, 509, 541, 571, 577, 587, 601, 617, 631, 641, 647, 691, 709, 739, 751, 757, 769, 787, 797, 809

Offset: 1

Author

David W. Wilson

Keywords

• nonn
• easy

Links

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

Crossrefs

Intersection of A153218 and A000040.

Cf. A153219.

Programs

Magma

[n: n in PrimesUpTo(900) | IsPrime(6*n+7)]; // Vincenzo Librandi, Nov 19 2010

Mathematica

Select[Prime[Range[200]],PrimeQ[6#+7]&] (* Harvey P. Dale, Nov 25 2012 *)

PARI

is(n)=isprime(6*n+7) && isprime(n) \\ Charles R Greathouse IV, Apr 18 2020