A171831 Primes p such that p and 3*p^2+3*p-1 are both prime.

2, 5, 7, 29, 37, 79, 89, 97, 107, 109, 127, 139, 149, 197, 229, 239, 277, 317, 379, 397, 487, 499, 509, 557, 587, 599, 607, 757, 769, 887, 907, 1019, 1049, 1069, 1097, 1297, 1307, 1439, 1499, 1559, 1567, 1609, 1619, 1637, 1667, 1709, 1759, 1847, 1979, 1997

Offset: 1

Author

Vincenzo Librandi, Dec 19 2009

Keywords

• nonn
• easy

Links

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

Programs

Magma

[p: p in PrimesUpTo(2000) | IsPrime(3*p^2+3*p-1)]; // Vincenzo Librandi, Dec 31 2013

Mathematica

Select[Prime[Range[500]],PrimeQ[3#^2+3#-1]&] (* Harvey P. Dale, Jul 24 2011 *)