A028957 Numbers represented by quadratic form with Gram matrix [ 2, 1; 1, 8 ] (divided by 2).

0, 1, 4, 6, 9, 10, 15, 16, 19, 24, 25, 31, 34, 36, 40, 46, 49, 51, 54, 60, 61, 64, 69, 76, 79, 81, 85, 90, 94, 96, 100, 106, 109, 114, 115, 121, 124, 135, 136, 139, 141, 144, 150, 151, 159, 160, 166, 169, 171, 181, 184, 186, 190, 196, 199, 204, 211, 214, 216, 225

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Comments

Nonnegative integers of the form x^2 + x*y + 4y^2, discriminant -15. - Ray Chandler, Jul 12 2014

Links

• N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

Crossrefs

Primes are in A033212.

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Mar 29 2000