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A243706 Primes represented by the indefinite quadratic form 3x^2+13xy-3y^2. 1
3, 7, 13, 17, 47, 53, 67, 97, 137, 157, 167, 193, 227, 233, 257, 263, 293, 313, 317, 347, 383, 397, 457, 463, 503, 547, 557, 563, 577, 587, 593, 643, 653, 673, 683, 727, 757, 773, 823, 827, 883, 887, 937, 967, 977, 997, 1013, 1063, 1093 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant 205.

12*a(n) has the form z^2 - 205*y^2, where z = 6*x+13*y. [Bruno Berselli, Jun 20 2014]

LINKS

Table of n, a(n) for n=1..49.

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

PROG

(PARI)

fc(a, b, c, M) = {

my(t1=List(), t2);

forprime(p=2, prime(M),

t2 = qfbsolve(Qfb(a, b, c), p);

if(t2 != 0, listput(t1, p))

);

Vec(t1)

};

fc(3, 13, -3, 600)

CROSSREFS

Primes in A243705.

Sequence in context: A214782 A032437 A076746 * A214696 A291661 A310256

Adjacent sequences:  A243703 A243704 A243705 * A243707 A243708 A243709

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 17 2014

STATUS

approved

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Last modified September 26 05:28 EDT 2022. Contains 356986 sequences. (Running on oeis4.)