A106866 Primes of the form 2x^2+xy+3y^2, with x and y nonnegative.

2, 3, 13, 41, 71, 127, 139, 179, 257, 269, 311, 331, 409, 439, 443, 461, 541, 587, 673, 739, 761, 823, 887, 967, 1051, 1061, 1087, 1129, 1153, 1223, 1237, 1277, 1373, 1381, 1409, 1427, 1439, 1567, 1619, 1733, 1741, 1783, 1933, 1973, 2017, 2063

Offset: 1

Author

T. D. Noe, May 09 2005

Keywords

• nonn
• easy

Comments

Discriminant=-23.

For even x we generate A309139. - R. J. Mathar, Aug 22 2019

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

Mathematica

QuadPrimes2[2, 1, 3, 10000] (* see A106856 *)