OFFSET
1,1
COMMENTS
Discriminant = -520. See A139827 for more information.
LINKS
Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 [First 1000 terms from Vincenzo Librandi]
N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)
FORMULA
The primes are congruent to {13, 23, 53, 77, 87, 103, 127, 133, 157, 173, 183, 207, 237, 263, 277, 287, 303, 367, 373, 407, 413, 477, 493, 503, 517} (mod 520).
MATHEMATICA
QuadPrimes2[10, 0, 13, 10000] (* see A106856 *)
PROG
(Magma) [ p: p in PrimesUpTo(3000) | p mod 520 in {13, 23, 53, 77, 87, 103, 127, 133, 157, 173, 183, 207, 237, 263, 277, 287, 303, 367, 373, 407, 413, 477, 493, 503, 517}]; // Vincenzo Librandi, Jul 29 2012
(PARI) list(lim)=my(v=List(), w, t); for(x=0, sqrtint(lim\10), w=10*x^2; for(y=1, sqrtint((lim-w)\13), if(isprime(t=w+13*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Mar 07 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 02 2008
STATUS
approved