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%I #18 Feb 10 2017 14:41:02
%S 97,181,277,337,349,373,613,733,757,829,853,1129,1213,1237,1297,1321,
%T 1549,1657,1693,1753,2017,2029,2089,2137,2221,2281,2521,2917,3037,
%U 3049,3181,3217,3229,3433,3469,3541,3697,3877,4093,4177,4549,4597
%N Primes of the form x^2 + 81y^2.
%C Discriminant = -324. See A107132 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A107193/b107193.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[1, 0, 81, 10000] (* see A106856 *)
%o (PARI) list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\1), w=x^2; for(y=1, sqrtint((lim-w)\81), if(isprime(t=w+81*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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