A107192 Primes of the form x^2 + 80y^2.

89, 401, 521, 761, 769, 809, 1009, 1049, 1249, 1289, 1361, 1409, 1601, 1721, 2081, 2089, 2441, 2729, 2801, 3001, 3049, 3089, 3121, 3169, 3329, 3529, 3881, 3929, 4001, 4049, 4201, 4289, 4441, 4561, 4649, 4729, 5009, 5081, 5209, 5281, 5441

Offset

1,1

Comments

Discriminant = -320. 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, 80, 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)\80), if(isprime(t=w+80*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017

Crossrefs

Sequence in context: A142448 A257118 A244777 * A061372 A254754 A083473

Adjacent sequences: A107189 A107190 A107191 * A107193 A107194 A107195

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Status

approved