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%I #17 Sep 08 2022 08:45:34
%S 31,71,151,239,271,359,431,479,631,839,1151,1279,1319,1399,1471,1831,
%T 1879,2039,2111,2351,2399,2671,2711,2719,2879,3079,3191,3271,3359,
%U 3391,3671,3911,3919,4231,4271,4519,4591,4639,4751,4799,4831,4919
%N Primes of the form 20x^2+20xy+31y^2.
%C Discriminant=-2080. See A139827 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A139975/b139975.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 The primes are congruent to {31, 71, 111, 119, 151, 239, 271, 279, 319, 359, 431, 479} (mod 520).
%t QuadPrimes2[20, -20, 31, 10000] (* see A106856 *)
%o (Magma) [p: p in PrimesUpTo(6000) | p mod 520 in [31, 71, 111, 119, 151, 239, 271, 279, 319, 359, 431, 479]]; // _Vincenzo Librandi_, Aug 03 2012
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 02 2008
%E Corrected and extended b-file - _Ray Chandler_, Aug 01 2014