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A309134 Nonnegative integers of the form x^2+12*x*y-y^2. 0
0, 1, 4, 9, 12, 16, 21, 25, 27, 28, 33, 36, 37, 44, 48, 49, 63, 64, 67, 77, 81, 84, 99, 100, 107, 108, 112, 121, 123, 132, 137, 139, 141, 144, 147, 148, 151, 159, 164, 169, 176, 188, 189, 192, 196, 212, 213, 219, 225, 231, 233, 243, 249, 252, 256, 268, 269, 284 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Discriminant of indefinite binary quadratic form: 148.

LINKS

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

Will Jagy, C++ program Conway_Positive_All.cc to find all positive numbers represented by an indefinite binary quadratic form

Peter Luschny, Binary Quadratic Forms

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

PROG

(C++) See Jagy link.

CROSSREFS

Primes in this sequence: A141163.

Sequence in context: A010449 A210607 A312857 * A312858 A312859 A045673

Adjacent sequences:  A309131 A309132 A309133 * A309135 A309136 A309137

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Jul 14 2019

STATUS

approved

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Last modified September 18 13:33 EDT 2020. Contains 337169 sequences. (Running on oeis4.)