A107146 Primes of the form 6x^2 + 7y^2.

7, 13, 31, 61, 103, 157, 181, 199, 223, 229, 271, 349, 367, 397, 439, 607, 661, 727, 733, 829, 853, 997, 1021, 1039, 1063, 1069, 1231, 1237, 1279, 1399, 1447, 1543, 1567, 1669, 1693, 1741, 1783, 1861, 1879, 1951, 2029, 2239, 2287, 2341, 2383

Offset

1,1

Comments

Discriminant = -168. 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)

Formula

The primes are congruent to {7, 13, 31, 55, 61, 103, 157} (mod 168). - T. D. Noe, May 02 2008

Mathematica

QuadPrimes2[6, 0, 7, 10000] (* see A106856 *)

Prog

(Magma) [ p: p in PrimesUpTo(3000) | p mod 168 in {7, 13, 31, 55, 61, 103, 157} ]; // Vincenzo Librandi, Jul 24 2012
(PARI) list(lim)=my(v=List([7]), s=[13, 31, 55, 61, 103, 157]); forprime(p=13, lim, if(setsearch(s, p%168), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Feb 09 2017

Crossrefs

Cf. A139827.

Sequence in context: A091431 A060800 A272204 * A201601 A284353 A129781

Adjacent sequences: A107143 A107144 A107145 * A107147 A107148 A107149

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Status

approved