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%I #18 Feb 10 2017 14:26:29
%S 19,23,83,163,271,367,419,479,491,503,571,619,919,947,967,1031,1051,
%T 1151,1187,1259,1327,1499,1543,1607,1619,1783,1831,2087,2239,2287,
%U 2399,2411,2531,2591,2671,2699,3083,3307,3323,3391,3407,3467,3847
%N Primes of the form 4x^2 + 19y^2.
%C Discriminant = -304. See A107132 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A107185/b107185.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[4, 0, 19, 10000] (* see A106856 *)
%o (PARI) list(lim)=my(v=List(),w,t); for(x=0, sqrtint(lim\4), w=4*x^2; for(y=1, sqrtint((lim-w)\19), if(isprime(t=w+19*y^2), listput(v,t)))); Set(v) \\ _Charles R Greathouse IV_, Feb 10 2017
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 13 2005
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