A201717 Primes of the form 3*m^2 - 5.

7, 43, 103, 967, 1447, 1723, 2347, 3067, 3463, 4327, 6343, 6907, 9403, 11527, 13063, 21163, 23227, 28807, 32443, 33703, 44647, 47623, 52267, 65707, 71143, 74887, 80683, 88747, 90823, 99367, 110587, 137383, 142567, 150523, 175687

Offset: 1

Author

Vincenzo Librandi, Dec 05 2011

Keywords

• nonn
• easy

Comments

Primes p such that 3*(p+5) or (p+5)/3 is a square. - Vincenzo Librandi, Feb 16 2016

Links

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

Crossrefs

Cf. A000040, A042993 (supersequence).

Cf. similar sequences: A089682, A201715, A201716, A201718, A201781.

Programs

Magma

[a: n in [2..300] | IsPrime(a) where a is 3*n^2-5];

Mathematica

Select[Table[3n^2-5,{n,2,1000}],PrimeQ]