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%I #18 Feb 10 2017 14:40:31
%S 5,61,109,149,269,389,421,661,701,821,829,1069,1181,1301,1381,1429,
%T 1901,1949,2141,2221,2269,2309,2341,2381,2549,2741,2749,2789,2909,
%U 3061,3109,3181,3221,3229,3541,3701,3709,4261,4349,4421,4909,5189
%N Primes of the form 5x^2 + 16y^2.
%C Discriminant = -320. See A107132 for more information.
%H Vincenzo Librandi and Ray Chandler, <a href="/A107191/b107191.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[5, 0, 16, 10000] (* see A106856 *)
%o (PARI) list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\5), w=5*x^2; for(y=0, sqrtint((lim-w)\16), if(isprime(t=w+16*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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