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Primes of the form 5x^2+xy+5y^2, with x and y any integer.
1

%I #20 Aug 05 2014 14:16:30

%S 5,11,23,47,53,59,71,89,113,137,179,191,251,257,269,311,317,353,383,

%T 389,401,419,443,449,467,509,521,587,599,617,641,647,653,683,719,773,

%U 797,839,863,881,911,929,947,971,977,983,1013,1049,1061,1103,1109

%N Primes of the form 5x^2+xy+5y^2, with x and y any integer.

%C Discriminant=-99.

%H Vincenzo Librandi and Ray Chandler, <a href="/A107010/b107010.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 Union[QuadPrimes2[5, 1, 5, 10000], QuadPrimes2[5, -1, 5, 10000]] (* see A106856 *)

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005