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Nonnegative integers of the form 2x^2 + 4xy - 3y^2.
1

%I #10 Jun 03 2022 14:55:44

%S 0,2,3,5,8,12,13,18,20,27,30,32,37,43,45,48,50,52,53,62,67,72,75,78,

%T 80,82,83,93,98,107,108,117,120,123,125,128,130,142,147,148,155,157,

%U 158,162,163,172,173,178,180,192,195,197,200,205,208,212,213,222,227,237,242,243,245,248,258,267,268,270,277,283

%N Nonnegative integers of the form 2x^2 + 4xy - 3y^2.

%C Discriminant 40.

%C From _Jon E. Schoenfield_, Jun 03 2022: (Start)

%C Also nonnegative integers of the form 5x^2 - 2y^2.

%C Also nonnegative integers of the form 2x^2 - 5y^2. (End)

%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)

%Y Primes in this sequence = A141179.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, May 31 2014