A020688 Numbers of form 5 x^2 + 9 y^2.

0, 5, 9, 14, 20, 29, 36, 41, 45, 54, 56, 80, 81, 86, 89, 101, 116, 125, 126, 134, 144, 149, 161, 164, 180, 189, 206, 216, 224, 225, 230, 245, 254, 261, 269, 270, 281, 305, 320, 324, 326, 329, 344, 350, 356, 369, 389, 401, 404, 405, 414, 441, 446, 449, 461, 464, 470, 486

Offset

1,2

Links

Table of n, a(n) for n=1..58.

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

Mathematica

Flatten[With[{nn=10}, Table[5x^2+9y^2, {x, 0, nn}, {y, 0, nn}]]]//Union (* Harvey P. Dale, May 21 2019 *)

Crossrefs

Sequence in context: A314973 A314974 A314975 * A314976 A314977 A314978

Adjacent sequences: A020685 A020686 A020687 * A020689 A020690 A020691

Keyword

easy,nonn

Author

David W. Wilson

Status

approved