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Primes of the form 7x^2 + 11y^2.
2

%I #18 Feb 10 2017 14:28:38

%S 7,11,107,127,211,239,263,547,571,739,743,919,1019,1163,1283,1471,

%T 1579,1583,1619,1667,1759,2111,2339,2503,2543,2683,2767,2879,3571,

%U 3607,3691,3739,3847,3907,4099,4111,4127,4391,4463,4831,4967,5147

%N Primes of the form 7x^2 + 11y^2.

%C Discriminant=-308. See A107132 for more information.

%H Vincenzo Librandi and Ray Chandler, <a href="/A107187/b107187.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[7, 0, 11, 10000] (* see A106856 *)

%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)\11), if(isprime(t=w+11*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