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A227939
Values of n such that the equation x^2 - 2*n*y^2 = n has integer solutions.
2
1, 3, 4, 9, 11, 12, 16, 19, 25, 27, 33, 36, 43, 44, 48, 49, 51, 57, 59, 64, 67, 73, 75, 76, 81, 83, 89, 99, 100, 107, 108, 121, 123, 129, 131, 132, 139, 144, 147, 163, 169, 171, 172, 176, 177, 179, 187, 192
OFFSET
1,2
LINKS
EXAMPLE
59 appears in the sequence because the equation x^2 - 118*y^2 = 59 has integer solutions.
MATHEMATICA
Select[Range[200], Length[FullSimplify[Solve[x^2-2*#*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