A257163 Primes of the form 3n^2 + 2.

2, 5, 29, 149, 509, 677, 1877, 3677, 8429, 9749, 11909, 13469, 17789, 22709, 27077, 28229, 45389, 46877, 53069, 70229, 72077, 81677, 100469, 102677, 114077, 128549, 141269, 154589, 180077, 192029, 195077, 207509, 223589, 230189, 261077, 312989, 340709, 352949, 395309, 399677, 426389

Offset: 1

Author

Juri-Stepan Gerasimov, Apr 16 2015

Keywords

• nonn
• easy

Comments

Two together with A027864(n).

Generated by n = 0, 1, 3, 7, 13, 15, 25, 35, 53, 57, ...

Examples

			2 is in this sequence because 3*0^2 + 2 = 2 and 2 is prime.
		

Crossrefs

Cf. A103564, A027864. Primes of the form k*n^2 + k - 1: A090698, this sequence, A121825, A201483, A201600, A201607, A201704.

Programs

Magma

[a: n in [0..400] | IsPrime(a) where a is (3*n^2+2)];

Mathematica

Select[Table[3 n^2 + 2, {n, 0, 400}], PrimeQ] (* Vincenzo Librandi, Apr 17 2015 *)

PARI

select(isprime, vector(100, n, 3*n^2-6*n+5)) \\ Charles R Greathouse IV, Apr 17 2015