OFFSET
1,1
COMMENTS
Discriminant=-91.
Also, primes that are squares (mod 91), or equivalently, with Legendre symbols (p|7) = (p|13) = 1. Included as subsequence in A191054 which are primes with Jacobi symbol (p|7*13) = 1, including also primes with (p|7) = (p|13) = -1. - David Broadhurst and M. F. Hasler, Jan 15 2016
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)
MATHEMATICA
QuadPrimes2[1, -1, 23, 10000] (* see A106856 *)
PROG
(PARI) is(p)=issquare(Mod(p, 91))&&isprime(p) \\ M. F. Hasler, Jan 15 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 09 2005
STATUS
approved