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%I #22 Sep 08 2022 08:45:33
%S 349,409,541,601,829,1021,1129,1381,1429,1549,1669,1741,1789,2221,
%T 2281,2341,2749,3049,3061,3109,3121,3169,3229,3301,3361,3709,3889,
%U 4129,4261,4441,4549,4861,4969,5101,5521,5569,5641,5689,5821,5869
%N Primes of the form x^2 + 345*y^2.
%C Discriminant = -1380. See A139643 for more information.
%C The primes are congruent to {1, 49, 121, 169, 289, 301, 349, 361, 409, 469, 541, 601, 721, 829, 841, 901, 949, 961, 1021, 1129, 1189, 1369} (mod 1380).
%H Vincenzo Librandi and Ray Chandler, <a href="/A139658/b139658.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, 345, 10000] (* see A106856 *)
%o (Magma) [ p: p in PrimesUpTo(7000) | p mod 1380 in {1, 49, 121, 169, 289, 301, 349, 361, 409, 469, 541, 601, 721, 829, 841, 901, 949, 961, 1021, 1129, 1189, 1369}]; // _Vincenzo Librandi_, Jul 29 2012
%o (Magma) k:=345; [p: p in PrimesUpTo(6000) | NormEquation(k, p) eq true]; // _Bruno Berselli_, Jun 01 2016
%K nonn,easy
%O 1,1
%A _T. D. Noe_, Apr 29 2008