A103776 Primes p such that 8*p^2 + 4*p + 1 is also prime.

2, 7, 11, 17, 41, 61, 101, 167, 227, 257, 281, 337, 347, 367, 397, 401, 461, 467, 487, 541, 571, 587, 601, 631, 641, 647, 661, 691, 701, 761, 857, 947, 971, 977, 997, 1021, 1087, 1237, 1277, 1291, 1381, 1451, 1481, 1607, 1621, 1627, 1667, 1697, 1787, 1811

Offset

1,1

Links

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

Mathematica

Select[Prime[Range[300]], PrimeQ[8 #^2 + 4 # + 1]&] (* Harvey P. Dale, Jan 04 2011 *)

Prog

(Magma) [n: n in [0..2000] | IsPrime(n) and IsPrime(8*n^2 + 4*n + 1)]; // Vincenzo Librandi, Feb 03 2014

Crossrefs

Cf. A102083.

Sequence in context: A109417 A045372 A273600 * A260889 A289994 A040154

Adjacent sequences: A103773 A103774 A103775 * A103777 A103778 A103779

Keyword

nonn,easy

Author

Zak Seidov, Feb 15 2005

Status

approved