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A243654 Nonnegative numbers represented by the indefinite quadratic form 3x^2+5xy-3y^2, of discriminant 61. 2
0, 1, 3, 4, 5, 9, 12, 13, 15, 16, 19, 20, 25, 27, 36, 39, 41, 45, 47, 48, 49, 52, 57, 60, 61, 64, 65, 73, 75, 76, 80, 81, 83, 95, 97, 100, 103, 107, 108, 109, 113, 117, 121, 123, 125, 127, 131, 135, 137, 141, 144, 147, 149, 156, 163, 164, 167, 169, 171, 179, 180, 183, 188, 192, 195, 196, 197, 199 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Also, nonnegative numbers represented by the indefinite quadratic form x^2-61y^2, of discriminant 244. The corresponding reduced form is x^2+14xy-12y^2.

Also 12*a(n) has the form z^2 - 61*y^2, where z = 6*x+5*y. [Bruno Berselli, Jun 20 2014]

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

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

MAPLE

select(t -> nops([isolve(x^2-61*y^2=t)])>0, [$0..200]); # Robert Israel, Jun 11 2014

PROG

(Other)

Computed using Will Jagy's C++ program Conway_Positive_All (see A243655 for the source code).

CROSSREFS

For primes see A141215.

Sequence in context: A010422 A287792 A050033 * A063953 A267755 A028952

Adjacent sequences:  A243651 A243652 A243653 * A243655 A243656 A243657

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 10 2014

STATUS

approved

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Last modified April 16 18:53 EDT 2021. Contains 343050 sequences. (Running on oeis4.)