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A229848
Values of n such that the equation x^2 - 3*n*y^2 = n has integer solutions.
2
1, 4, 7, 9, 13, 16, 19, 25, 28, 31, 36, 37, 43, 49, 52, 61, 63, 64, 67, 76, 79, 81, 91, 100, 103, 109, 112, 117, 121, 124, 127, 139, 144, 148, 151, 157, 163, 169, 171, 172, 175, 181, 193, 196, 199, 208, 211, 217, 223, 225, 229, 244, 247, 252, 256, 268, 271
OFFSET
1,2
EXAMPLE
37 appears in the sequence because the equation x^2 - 111*y^2 = 37 has integer solutions.
MATHEMATICA
Select[Range[300], Length[FullSimplify[Solve[x^2-3*#*y^2==#, {x, y}, Integers]/.C[1]->1]]>0&] (* Vaclav Kotesovec, Oct 08 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Colin Barker, Oct 07 2013
STATUS
approved