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A243173 Numbers of the form x^2+15y^2. 3
0, 1, 4, 9, 15, 16, 19, 24, 25, 31, 36, 40, 49, 51, 60, 61, 64, 69, 76, 79, 81, 85, 96, 100, 109, 115, 121, 124, 135, 136, 139, 141, 144, 151, 159, 160, 169, 171, 181, 184, 196, 199, 204, 211, 216, 225, 229, 235, 240, 241, 244, 249, 256, 265, 271, 276, 279, 285, 289, 304, 316, 321, 324, 331, 339, 340, 349, 360, 361, 375, 376, 379, 384, 391, 400, 409, 411 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Discriminant -60.

Norms of numbers in Z[sqrt(-15)]. - Alonso del Arte, Sep 23 2014

LINKS

Bruno Berselli, Table of n, a(n) for n = 1..1000

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

MATHEMATICA

nn = 22; Union[Select[Flatten[Table[x^2 + 15 y^2, {x, 0, nn}, {y, 0, nn}]], # <= nn^2 &]] (* Bruno Berselli, Jun 02 2014 *)

CROSSREFS

Primes: A033212.

Sequence in context: A122499 A143709 A010446 * A345452 A313156 A309136

Adjacent sequences:  A243170 A243171 A243172 * A243174 A243175 A243176

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 01 2014

STATUS

approved

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Last modified August 1 22:36 EDT 2021. Contains 346408 sequences. (Running on oeis4.)