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Nonnegative integers of the form 5*x^2 + 5*x*y - y^2.
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%I #8 Jun 03 2022 18:09:23

%S 0,5,9,11,20,29,36,41,44,45,59,71,80,81,89,95,99,101,116,125,131,144,

%T 149,155,164,171,176,179,180,191,209,225,236,239,245,251,261,269,275,

%U 279,281,284,305,311,320,324,341,356,359,369,380,389,395,396,401,404

%N Nonnegative integers of the form 5*x^2 + 5*x*y - y^2.

%C Equivalent quadratic form: 9*x^2+15*x*y+5*y^2.

%C Discriminant of indefinite binary quadratic form: 45.

%C Nonnegative numbers of the form 5x^2 - 9y^2. - _Jon E. Schoenfield_, Jun 03 2022

%H Will Jagy, <a href="/A243655/a243655.txt">C++ program Conway_Positive_All.cc to find all positive numbers represented by an indefinite binary quadratic form</a>

%H Peter Luschny, <a href="https://oeis.org/wiki/User:Peter_Luschny/BinaryQuadraticForms#Implementation">Binary Quadratic Forms</a>

%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)

%o (C++) See Jagy link.

%Y Primes in this sequence: A141785.

%K nonn

%O 1,2

%A _Hugo Pfoertner_, Jul 14 2019