A106015 Primes p such that 4*p +- 3 are primes.

2, 5, 11, 19, 59, 89, 109, 149, 151, 331, 359, 389, 401, 439, 499, 521, 571, 599, 829, 941, 1019, 1039, 1129, 1249, 1279, 1319, 1381, 1451, 1669, 1741, 1871, 2131, 2161, 2179, 2251, 2459, 2819, 3119, 3251, 3469, 3539, 3581, 3659, 3911, 4001, 4231, 4261

Offset: 1

Author

Zak Seidov, May 05 2005

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Programs

Magma

[p: p in PrimesUpTo(100000)| IsPrime(4*p-3) and IsPrime(4*p+3)]; // Vincenzo Librandi, Nov 13 2010

Mathematica

Select[Prime[Range[400]], PrimeQ[4#+3]&&PrimeQ[4#-3]&]
Select[Prime[Range[600]],AllTrue[4#+{3,-3},PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Feb 18 2021 *)

Formula

A023213 INTERSECT A157978. - R. J. Mathar, Jul 25 2009