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Primes of the form 4x^2 + 17y^2.
2

%I #19 Feb 10 2017 11:58:31

%S 17,53,157,349,409,461,569,593,829,937,977,1381,1409,1597,1721,1733,

%T 1753,1777,1861,2053,2089,2129,2161,2269,2381,2633,2729,2857,2909,

%U 2957,3137,3313,3449,3517,3617,3821,3877,3889,4021,4373,4513,4637

%N Primes of the form 4x^2 + 17y^2.

%C Discriminant = -272. See A107132 for more information.

%H Vincenzo Librandi and Ray Chandler, <a href="/A107175/b107175.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, 17, 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)\17), if(isprime(t=w+17*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