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A035269 Indices of nonzero terms in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m= 41. 1
1, 2, 4, 5, 8, 9, 10, 16, 18, 20, 23, 25, 31, 32, 36, 37, 40, 41, 43, 45, 46, 49, 50, 59, 61, 62, 64, 72, 73, 74, 80, 81, 82, 83, 86, 90, 92, 98, 100, 103, 107, 113, 115, 118, 121, 122, 124, 125, 127, 128, 131, 139, 144, 146, 148, 155, 160, 162, 163, 164 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also, positive numbers represented by 2x^2+3xy-4y^2, discriminant 41.

LINKS

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

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

MATHEMATICA

Reap[For[n = 0, n <= 100, n++, If[Reduce[ 2*x^2 + 3*x*y - 4*y^2 == n, {x, y}, Integers] =!= False, Sow[n]]]][[2, 1]] (* N. J. A. Sloane, Jun 05 2014 *)

PROG

(PARI) m=41; select(x -> x, direuler(p=2, 101, 1/(1-(kronecker(m, p)*(X-X^2))-X)), 1) \\ Fixed by Andrey Zabolotskiy, Jul 30 2020

CROSSREFS

Primes: A141181.

Cf. A035223.

Sequence in context: A340956 A010402 A010443 * A267703 A277075 A038558

Adjacent sequences:  A035266 A035267 A035268 * A035270 A035271 A035272

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Colin Barker, Jun 17 2014

STATUS

approved

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Last modified December 1 09:39 EST 2021. Contains 349426 sequences. (Running on oeis4.)