A139877 Primes of the form 8x^2+21y^2.

29, 53, 149, 197, 317, 389, 557, 653, 701, 821, 1061, 1229, 1373, 1493, 1709, 1733, 1877, 1901, 1997, 2069, 2213, 2237, 2333, 2381, 2549, 2741, 2837, 2909, 3221, 3389, 3413, 3557, 3581, 3677, 3917, 4013, 4229, 4253, 4349, 4397, 4421, 4517

Offset: 1

Author

T. D. Noe, May 02 2008

Keywords

• nonn
• easy

Comments

Discriminant=-672. See A139827 for more information.

Also primes of the form 29x^2+12xy+36y^2. See A140633. - T. D. Noe, May 19 2008

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

[ p: p in PrimesUpTo(6000) | p mod 168 in {29, 53, 149}]; // Vincenzo Librandi, Jul 30 2012

Mathematica

QuadPrimes2[8, 0, 21, 10000] (* see A106856 *)

Formula

The primes are congruent to {29, 53, 149} (mod 168).