A107171 Primes of the form 5x^2 + 13y^2.

5, 13, 97, 137, 193, 197, 457, 593, 613, 617, 733, 877, 1097, 1237, 1373, 1553, 1753, 1877, 1913, 1997, 2273, 2293, 2333, 2377, 2477, 2593, 2917, 2953, 3037, 3373, 3517, 3593, 3673, 3677, 3697, 3733, 3853, 4217, 4337, 4457, 4513, 4517, 4673

Offset

1,1

Comments

Discriminant = -260. 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[5, 0, 13, 10000] (* see A106856 *)

Prog

(PARI) list(lim)=my(v=List(), w, t); for(x=0, sqrtint(lim\5), w=5*x^2; for(y=0, sqrtint((lim-w)\13), if(isprime(t=w+13*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017

Crossrefs

Sequence in context: A280294 A304663 A306167 * A309532 A123646 A123622

Adjacent sequences: A107168 A107169 A107170 * A107172 A107173 A107174

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Status

approved