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Primes of the form 2x^2+xy+7y^2, with x and y any integer.
1

%I #20 Aug 05 2014 14:16:29

%S 2,7,13,17,43,73,83,107,127,167,173,193,197,227,233,263,277,283,293,

%T 307,337,347,373,457,503,523,547,557,563,593,607,613,673,677,733,743,

%U 787,827,853,857,877,887,937,953,967,997,1033,1063,1097,1117,1163

%N Primes of the form 2x^2+xy+7y^2, with x and y any integer.

%C Discriminant=-55.

%H Vincenzo Librandi and Ray Chandler, <a href="/A106911/b106911.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[2, 1, 7, 10000], QuadPrimes2[2, -1, 7, 10000]] (* see A106856 *)

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005