A139876 Primes of the form 7x^2+24y^2.

7, 31, 103, 199, 223, 271, 367, 439, 607, 727, 1039, 1063, 1231, 1279, 1399, 1447, 1543, 1567, 1783, 1879, 1951, 2239, 2287, 2383, 2551, 2719, 2791, 2887, 3079, 3391, 3463, 3559, 3583, 3631, 3727, 3919, 3967, 4231, 4423, 4567, 4591, 4639

Offset: 1

Author

T. D. Noe, May 02 2008

Keywords

• nonn
• easy

Comments

Discriminant=-672. See A139827 for more information.

Links

• Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 [First 1000 terms from Vincenzo Librandi]
• N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

Programs

Magma

[7] cat [ p: p in PrimesUpTo(6000) | p mod 168 in {31, 55, 103}]; // Vincenzo Librandi, Jul 30 2012

Mathematica

QuadPrimes2[7, 0, 24, 10000] (* see A106856 *)

Formula

Except for 7, the primes are congruent to {31, 55, 103} (mod 168).