A107185 Primes of the form 4x^2 + 19y^2.

19, 23, 83, 163, 271, 367, 419, 479, 491, 503, 571, 619, 919, 947, 967, 1031, 1051, 1151, 1187, 1259, 1327, 1499, 1543, 1607, 1619, 1783, 1831, 2087, 2239, 2287, 2399, 2411, 2531, 2591, 2671, 2699, 3083, 3307, 3323, 3391, 3407, 3467, 3847

Offset

1,1

Comments

Discriminant = -304. 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[4, 0, 19, 10000] (* see A106856 *)

Prog

(PARI) list(lim)=my(v=List(), w, t); for(x=0, sqrtint(lim\4), w=4*x^2; for(y=1, sqrtint((lim-w)\19), if(isprime(t=w+19*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017

Crossrefs

Sequence in context: A043895 A288614 A033214 * A240585 A226607 A284495

Adjacent sequences: A107182 A107183 A107184 * A107186 A107187 A107188

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Status

approved