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%I #16 Sep 08 2022 08:45:34
%S 13,53,157,173,277,373,653,677,757,797,997,1013,1093,1117,1213,1277,
%T 1453,1613,1637,1693,1733,1933,1973,2053,2213,2237,2357,2557,2677,
%U 2837,3253,3533,3613,3637,3797,3877,3917,4013,4133,4157,4397,4637
%N Primes of the form 13x^2+40y^2.
%C Discriminant=-2080. See A139827 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A139974/b139974.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 13, the primes are congruent to {53, 77, 133, 157, 173, 237, 277, 373, 413, 477, 493, 517} (mod 520).
%t QuadPrimes2[13, 0, 40, 10000] (* see A106856 *)
%o (Magma) [13] cat [p: p in PrimesUpTo(6000) | p mod 520 in [53, 77, 133, 157, 173, 237, 277, 373, 413, 477, 493, 517]]; // _Vincenzo Librandi_, Aug 03 2012
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 02 2008