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%I #10 Jun 03 2022 14:56:00
%S 0,1,2,4,8,9,11,16,18,22,25,32,35,36,43,44,49,50,64,65,67,70,72,81,86,
%T 88,91,98,99,100,107,113,121,128,130,134,137,140,144,155,162,163,169,
%U 172,176,179,182,193,196,198,200
%N Nonnegative integers of the form x^2 + 6xy - 5y^2.
%C Discriminant 56.
%C Nonnegative integers of the form 2x^2 - 7y^2. - _Jon E. Schoenfield_, Jun 03 2022
%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 Reap[For[n = 0, n <= 200, n++, If[Reduce[1*x^2 + 6*x*y - 5*y^2 == n, {x, y}, Integers] =!= False, Sow[n]]]][[2, 1]]
%Y Primes: A141190.
%K nonn
%O 1,3
%A _N. J. A. Sloane_, Jun 05 2014