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%I #18 Sep 08 2022 08:45:34
%S 7,19,47,83,131,139,199,251,271,283,311,367,419,467,479,503,587,619,
%T 643,647,691,719,727,859,1151,1223,1259,1279,1483,1487,1531,1543,1559,
%U 1567,1783,1811,1847,1867,1879,1907,1987,2063,2099,2239,2243,2267
%N Primes of the form 7x^2 + 19y^2.
%C Discriminant=-532. See A139827 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A139865/b139865.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 {7, 19, 47, 55, 83, 87, 111, 115, 131, 139, 159, 187, 195, 199, 215, 251, 271, 283, 311, 327, 339, 367, 391, 419, 423, 467, 479, 495, 503} (mod 532).
%t QuadPrimes2[7, 0, 19, 10000] (* see A106856 *)
%o (Magma) [ p: p in PrimesUpTo(3000) | p mod 532 in {7, 19, 47, 55, 83, 87, 111, 115, 131, 139, 159, 187, 195, 199, 215, 251, 271, 283, 311, 327, 339, 367, 391, 419, 423, 467, 479, 495, 503}]; // _Vincenzo Librandi_, Jul 29 2012
%o (PARI) list(lim)=my(v=List(),w,t); for(x=0, sqrtint(lim\7), w=7*x^2; for(y=0, sqrtint((lim-w)\19), if(isprime(t=w+19*y^2), listput(v,t)))); Set(v) \\ _Charles R Greathouse IV_, Mar 07 2017
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 02 2008
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