A106877 Primes of the form 3x^2+xy+3y^2, with x and y nonnegative.

3, 7, 17, 83, 97, 157, 173, 223, 257, 307, 313, 397, 523, 587, 607, 643, 647, 733, 773, 787, 887, 937, 983, 1013, 1223, 1277, 1307, 1427, 1483, 1487, 1613, 1637, 1693, 1753, 1777, 1783, 1907, 2203, 2267, 2273, 2357, 2383, 2393, 2593, 2663, 2677

Offset: 1

Author

T. D. Noe, May 09 2005

Keywords

• nonn
• easy

Comments

Discriminant=-35.

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. A106878.

Programs

Mathematica

QuadPrimes2[3, 1, 3, 10000] (* see A106856 *)