A155737 Primes of the form 4*n^2 + 2*n -1.

5, 19, 41, 71, 109, 271, 419, 599, 701, 811, 929, 1481, 1979, 2161, 2351, 2549, 2969, 3191, 3659, 4159, 4421, 4691, 4969, 5851, 7481, 8929, 9311, 10099, 13109, 14519, 16001, 17029, 18089, 19181, 19739, 20879, 22051, 23869, 25121, 25759, 27059

Offset: 1

Author

Vincenzo Librandi, Jan 26 2009

Keywords

• nonn
• easy

Comments

Primes in A125202. - Klaus Purath, Dec 09 2020

Links

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

Crossrefs

Cf. A155736, A155738, A125202.

Programs

Magma

[a: n in [0..100] | IsPrime(a) where a is  4*n^2+2*n-1]; // Vincenzo Librandi, Jul 23 2012

Mathematica

Select[Table[4n^2+2n-1,{n,0,200}],PrimeQ] (* Vincenzo Librandi, Jul 23 2012 *)

PARI

(for (n=0, 100, if (isprime (k=4*n^2+2*n-1), print1 (k, ", ")))); \\ Vincenzo Librandi, Jul 23 2012

Extensions

Incorrect formula deleted by N. J. A. Sloane, Jun 16 2010