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%I #7 Jun 19 2014 15:19:04
%S 43,67,127,151,331,373,421,457,463,613,631,739,757,883,919,967,1033,
%T 1087,1171,1327,1381,1429,1453,1471,1549,1579,1597,1747,1759,1789,
%U 1801,2053,2083,2143,2269,2293,2311,2347,2389,2473,2503,2671,2767,2797,2857
%N Primes of the form x^2 + 19x*y + y^2 for x and y nonnegative.
%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 a = {}; w = 19; k = 1; Do[Do[If[PrimeQ[n^2 + w*n*m + k*m^2], AppendTo[a, n^2 + w*n*m + k*m^2]], {n, m, 400}], {m, 1, 400}]; Union[a] (*Artur Jasinski*)
%t upto=3000;With[{max=Ceiling[Sqrt[upto]]},Select[Union[Select[(First[#]^2+ 19First[#]Last[#]+ Last[#]^2)&/@(Tuples[Range[0,max],{2}]), PrimeQ]], #<+upto&]] (* _Harvey P. Dale_, Jul 20 2011 *)
%Y Cf. A139489, A007645, A068228, A007519, A033212, A033212, A107152, A107008, A033215, A107145, A139490, A139491.
%K nonn
%O 1,1
%A _Artur Jasinski_, Apr 24 2008