A175063 Primes p such that 5*p^2 + 5*p + 1 is also prime.

2, 3, 5, 7, 11, 13, 17, 19, 43, 61, 71, 73, 79, 101, 107, 109, 127, 131, 137, 139, 149, 151, 167, 191, 193, 239, 263, 269, 283, 311, 347, 373, 379, 389, 401, 433, 439, 443, 461, 479, 499, 541, 587, 641, 643, 659, 701, 719, 733, 773, 797, 821, 883, 887, 907, 919

Offset: 1

Author

Vincenzo Librandi, Dec 20 2009

Keywords

• nonn

Links

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

Crossrefs

Cf. A000040, A090563.

Programs

Mathematica

Select[Prime[Range[200]],PrimeQ[5#^2+5#+1]&]  (* Harvey P. Dale, Feb 25 2011 *)

Formula

A090563 INTERSECT A000040. - R. J. Mathar, Jul 06 2010

Extensions

Corrected title. - Joerg Arndt, Mar 11 2010