A028957 - OEIS

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

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OFFSET

1,3

COMMENTS

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

LINKS

Table of n, a(n) for n=1..60.

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

CROSSREFS

Primes are in A033212.

Sequence in context: A310665 A005659 A010462 * A242664 A084662 A137167

Adjacent sequences: A028954 A028955 A028956 * A028958 A028959 A028960