A106906 Primes of the form 2x^2-2xy+7y^2, with x and y nonnegative.

2, 7, 11, 19, 31, 47, 59, 67, 71, 83, 151, 163, 167, 223, 227, 239, 271, 307, 331, 359, 379, 383, 431, 463, 479, 487, 499, 587, 619, 631, 643, 683, 691, 739, 743, 787, 811, 827, 839, 863, 947, 967, 983, 1019, 1051, 1087, 1103, 1123, 1151, 1163, 1259, 1279

Offset: 1

Author

T. D. Noe, May 09 2005

Keywords

• nonn
• easy

Comments

Discriminant=-52.

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)

Crossrefs

Cf. A139827.

Programs

Mathematica

QuadPrimes2[2, -2, 7, 10000] (* see A106856 *)

Formula

The primes are congruent to {2, 7, 11, 15, 19, 31, 47} (mod 52). - T. D. Noe, May 02 2008