To get all numbers that are primitively represented by x^2+0xy-2y^2 in the range 1 to 10: $ ./Conway_Positive_Primitive 1 0 -2 10 1 0 -2 original form 1 2 -1 Lagrange-Gauss reduced 1 4 2 insert_primitive_reps 1 6 7 insert_primitive_reps 7 8 2 insert_primitive_reps 2 4 1 insert_primitive_reps 2 8 7 insert_primitive_reps 7 6 1 insert_primitive_reps Primitively represented positive integers up to 10 1 = 1 2 = 2 7 = 7 Primitively represented positive integers up to 10 1 0 -2 original form