A139657 - OEIS

%I #22 Sep 08 2022 08:45:33

%S 331,379,499,619,691,859,1171,1291,1321,1489,1609,1699,2011,2161,2179,

%T 2281,2539,2689,2731,2971,3001,3019,3169,3259,3331,3499,3529,3931,

%U 4051,4129,4339,4651,4801,5179,5281,5449,5569,5641,5659,5779,6121

%N Primes of the form x^2 + 330*y^2.

%C Discriminant=-1320. See A139643 for more information.

%C The primes are congruent to {1, 49, 91, 169, 289, 331, 361, 379, 499, 529, 619, 691, 841, 859, 889, 961, 1081, 1171, 1219, 1291} (mod 1320).

%H Vincenzo Librandi and Ray Chandler, <a href="/A139657/b139657.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Vincenzo Librandi).

%H N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)

%t QuadPrimes2[1, 0, 330, 10000] (* see A106856 *)

%o (Magma) [ p: p in PrimesUpTo(7000) | p mod 1320 in {1, 49, 91, 169, 289, 331, 361, 379, 499, 529, 619, 691, 841, 859, 889, 961, 1081, 1171, 1219, 1291}]; // _Vincenzo Librandi_, Jul 29 2012

%o (Magma) k:=330; [p: p in PrimesUpTo(6200) | NormEquation(k, p) eq true]; // _Bruno Berselli_, Jun 01 2016

%K nonn,easy

%O 1,1

%A _T. D. Noe_, Apr 29 2008