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A028957 Numbers represented by quadratic form with Gram matrix [ 2, 1; 1, 8 ] (divided by 2). 3
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 (list; graph; refs; listen; history; text; internal format)
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

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

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

STATUS

approved

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Last modified July 25 03:53 EDT 2021. Contains 346283 sequences. (Running on oeis4.)