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%I #17 Sep 08 2022 08:45:33
%S 2,23,47,83,107,167,227,263,347,383,443,467,503,563,587,647,683,743,
%T 827,863,887,947,983,1103,1163,1187,1223,1283,1307,1367,1427,1487,
%U 1523,1583,1607,1667,1787,1823,1847,1907,2003,2027,2063,2087,2207
%N Primes of the form 2x^2+2xy+23y^2.
%C Discriminant=-180. See A139827 for more information.
%C Except for 2, also primes of the forms 3x^2+20y^2 (A107169) and 8x^2+4xy+23y^2. See A140633. - _T. D. Noe_, May 19 2008
%H Vincenzo Librandi and Ray Chandler, <a href="/A139831/b139831.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)
%F Except for 2, the primes are congruent to {23, 47} (mod 60).
%t QuadPrimes2[2, -2, 23, 10000] (* see A106856 *)
%o (Magma) [2] cat[ p: p in PrimesUpTo(3000) | p mod 60 in {23, 47}]; // _Vincenzo Librandi_, Jul 29 2012
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 02 2008