A007637 Primes of form 3*k^2 - 3*k + 23.

23, 29, 41, 59, 83, 113, 149, 191, 239, 293, 353, 419, 491, 569, 653, 743, 839, 941, 1049, 1163, 1283, 1409, 1823, 1973, 2129, 2459, 2633, 2999, 3191, 3389, 3593, 3803, 4019, 4241, 4703, 4943, 5189, 5441, 6791, 7079, 7673, 8291, 8609

Offset: 1

Author

N. J. A. Sloane, Mira Bernstein, Robert G. Wilson v

Keywords

• nonn
• easy

References

• Paul Hoffman, Archimedes' Revenge, Penguin Books 1988, pp. 39-40.
• Paulo Ribenboim, The Little Book of Bigger Primes, Springer-Verlag NY 2004. See p. 145.
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• Harvey Dubner, Generalized Cullen numbers, J. Rec. Math., 21 (No. 3, 1989), 190-191. (Annotated scanned copy)

Crossrefs

Cf. A007638.

Programs

Magma

[a: n in [1..60] | IsPrime(a) where a is 3*n^2-3*n+23]; // Vincenzo Librandi, Mar 20 2013

Mathematica

Select[Table[3 n^2 - 3 n + 23, {n, 60}], PrimeQ] (* Vincenzo Librandi, Mar 20 2013 *)