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A243706
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Primes represented by the indefinite quadratic form 3x^2+13xy-3y^2.
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1
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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
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OFFSET
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1,1
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COMMENTS
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Discriminant 205.
12*a(n) has the form z^2 - 205*y^2, where z = 6*x+13*y. [Bruno Berselli, Jun 20 2014]
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LINKS
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PROG
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(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)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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