A201715 Primes of the form 3*m^2 - 2.

73, 241, 673, 1321, 1873, 2521, 3673, 4561, 6073, 11161, 14281, 15121, 19681, 21673, 23761, 24841, 27073, 29401, 33073, 49921, 51481, 54673, 63073, 66601, 72073, 77761, 87721, 91873, 102673, 109441, 114073, 118801, 131041, 143881

Offset: 1

Author

Vincenzo Librandi, Dec 04 2011

Keywords

• nonn
• easy

Comments

Primes p such that 3*(p+2) or (p+2)/3 is a square. - Vincenzo Librandi, Feb 16 2016

m is a member of A063213. - Bruno Berselli, Feb 16 2016

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..5000

Crossrefs

Primes in A100536.

Cf. A089682, A201716, A201717, A201718, A201781.

Programs

Magma

[a: n in [1..300] | IsPrime(a) where a is 3*n^2-2];

Mathematica

Select[Table[3 n^2 - 2, {n, 1, 800}], PrimeQ]