A107176 Primes of the form x^2 + 68y^2.

149, 281, 293, 353, 509, 613, 661, 733, 797, 1097, 1237, 1361, 1453, 1709, 2141, 2293, 2297, 2473, 2609, 2617, 2789, 3221, 3413, 3557, 3637, 3673, 4093, 4129, 4241, 4297, 4337, 4421, 4657, 4793, 5081, 5101, 5441, 5557, 5653, 5669, 5693

Offset

1,1

Comments

Discriminant = -272. See A107132 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)

Mathematica

QuadPrimes2[1, 0, 68, 10000] (* see A106856 *)

Prog

(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\1), w=x^2; for(y=1, sqrtint((lim-w)\68), if(isprime(t=w+68*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017

Crossrefs

Sequence in context: A142687 A142825 A127592 * A140023 A105843 A131573

Adjacent sequences: A107173 A107174 A107175 * A107177 A107178 A107179

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Status

approved