A171139 Primes p such that 7*p^2+7*p-1 is also prime.

2, 3, 17, 19, 23, 29, 47, 67, 73, 97, 113, 151, 163, 173, 223, 227, 229, 239, 251, 257, 263, 311, 331, 359, 367, 373, 389, 409, 419, 433, 439, 457, 463, 491, 503, 523, 541, 563, 569, 607, 701, 733, 809, 853, 877, 883, 941, 953, 967, 983, 1013, 1033, 1049

Offset

1,1

Links

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

Mathematica

Select[Prime[Range[200]], PrimeQ[7 #^2 + 7 # - 1]&] (* Vincenzo Librandi, Apr 16 2013 *)

Prog

(Magma) [p: p in PrimesUpTo(1050) | IsPrime(7*p^2+7*p-1)]; // Vincenzo Librandi, Apr 16 2013

Crossrefs

Cf. A171138.

Sequence in context: A361104 A090913 A176236 * A291281 A135931 A215323

Adjacent sequences: A171136 A171137 A171138 * A171140 A171141 A171142

Keyword

nonn,easy

Author

Vincenzo Librandi, Jan 26 2010

Status

approved