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 A243174 Nonnegative integers of the form x^2 + 5*x*y - 5*y^2 (discriminant 45). 4
 0, 1, 4, 9, 16, 19, 25, 31, 36, 45, 49, 55, 61, 64, 76, 79, 81, 99, 100, 109, 121, 124, 139, 144, 145, 151, 169, 171, 180, 181, 196, 199, 205, 211, 220, 225, 229, 241, 244, 256, 261, 271, 279, 289, 295, 304, 316, 319, 324, 331, 349, 355, 361, 369, 379, 396, 400, 405, 409, 421, 436, 439, 441, 445, 451, 475, 484, 495, 496, 499, 505, 529, 531, 541, 549 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Also numbers representable as x^2 + 7*x*y + y^2 with 0 <= x <= y. - Gheorghe Coserea, Jul 29 2018 Also numbers of the form x^2 - x*y - 11*y^2 with 0 <= x <= y (or x^2 + x*y - 11*y^2 with x, y nonnegative). - Jianing Song, Jul 31 2018 LINKS Gheorghe Coserea, Table of n, a(n) for n = 1..100001 N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references) CROSSREFS Cf. A028957, A031363. Primes: A033212. Sequence in context: A035234 A313325 A313326 * A313327 A313328 A313329 Adjacent sequences:  A243171 A243172 A243173 * A243175 A243176 A243177 KEYWORD nonn AUTHOR N. J. A. Sloane, Jun 01 2014 STATUS approved

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Last modified July 28 22:55 EDT 2021. Contains 346340 sequences. (Running on oeis4.)