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A279587
Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = sqrt(2).
1
1, -2, 0, 3, -3, 0, 4, -7, 5, 5, -16, 15, 2, -26, 39, -19, -38, 92, -77, -34, 178, -220, 48, 293, -537, 343, 363, -1129, 1146, 94, -2050, 3029, -1290, -3039, 6855, -5577, -2738, 13513, -16417, 3007, 22633, -40108, 24584, 28535, -85117, 84600, 10247, -156524
OFFSET
0,2
LINKS
FORMULA
G.f.: 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = sqrt(2).
MATHEMATICA
z = 30; r = Sqrt[2];
f[x_] := f[x] = Sum[Floor[r*(k + 1)] x^k, {k, 0, z}]; f[x]
CoefficientList[Series[1/f[x], {x, 0, 2*z}], x] (* A279587 *)
CROSSREFS
Cf. A001951.
Sequence in context: A325191 A209703 A279779 * A127952 A171307 A372817
KEYWORD
sign,easy
AUTHOR
Clark Kimberling, Dec 15 2016
STATUS
approved