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Primes of the form x^2+xy+20y^2, with x and y nonnegative.
2

%I #17 Aug 05 2014 14:16:29

%S 83,179,223,397,479,541,563,677,727,757,811,863,907,941,967,1103,1277,

%T 1289,1433,1489,1523,1553,1867,1889,1993,1997,2011,2039,2311,2341,

%U 2383,2459,2551,2579,2633,2647,2917,2999,3271,3373,3469,3739,3797

%N Primes of the form x^2+xy+20y^2, with x and y nonnegative.

%C Discriminant=-79.

%H Vincenzo Librandi and Ray Chandler, <a href="/A106962/b106962.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[1, 1, 20, 10000] (* see A106856 *)

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 09 2005