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A309135 Nonnegative integers of the form 9*x^2+7*x*y-5*y^2. 0
0, 3, 5, 9, 11, 12, 15, 17, 19, 20, 25, 27, 33, 36, 43, 44, 45, 48, 51, 55, 57, 60, 61, 68, 71, 75, 76, 80, 81, 83, 85, 95, 97, 99, 100, 103, 108, 111, 121, 125, 129, 132, 135, 144, 147, 149, 151, 153, 159, 165, 167, 171, 172, 176, 180, 181, 183, 185, 187, 192 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Discriminant of indefinite binary quadratic form: 229.

LINKS

Table of n, a(n) for n=1..60.

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: A141165.

Sequence in context: A323765 A270780 A304251 * A088607 A296243 A162699

Adjacent sequences:  A309132 A309133 A309134 * A309136 A309137 A309138

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Jul 14 2019

STATUS

approved

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Last modified April 20 09:21 EDT 2021. Contains 343125 sequences. (Running on oeis4.)