A154319 Primes p such that p^2 + 2*p - 4 is also prime.

3, 5, 7, 11, 13, 23, 31, 37, 41, 43, 71, 73, 101, 131, 151, 163, 167, 173, 181, 197, 211, 233, 251, 263, 277, 283, 317, 353, 373, 383, 401, 431, 433, 467, 491, 547, 557, 571, 587, 593, 607, 643, 653, 701, 727, 733, 761, 823, 857, 881, 907, 911, 937, 983, 991

Offset

1,1

Links

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

Mathematica

Select[Prime[Range[1000]], PrimeQ[#^2 + 2*# - 4]&] (* Vincenzo Librandi, Oct 30 2012 *)

Prog

(Magma) [p: p in PrimesUpTo(1500)| IsPrime(p^2 + 2*p - 4)]; // Vincenzo Librandi, Oct 30 2012

Crossrefs

Cf. A154320, A154321.

Sequence in context: A182583 A181741 A350401 * A080114 A088878 A259730

Adjacent sequences: A154316 A154317 A154318 * A154320 A154321 A154322

Keyword

nonn,easy

Author

Vincenzo Librandi, Jan 07 2009

Status

approved