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A279778
Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 6/5.
5
1, -2, 1, 0, -1, 3, -3, 1, 1, -5, 9, -7, 1, 7, -19, 25, -15, -5, 33, -63, 65, -25, -43, 129, -191, 155, -7, -215, 449, -537, 317, 201, -879, 1435, -1391, 433, 1281, -3193, 4261, -3215, -415, 5755, -10647, 11737, -6015, -6585, 22157, -33031, 29489, -5445
OFFSET
0,2
FORMULA
G.f.: 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 6/5.
G.f.: (1 - x) (1 - x^5)/(1 + x + x^2 + x^3 + 2 x^4).
MATHEMATICA
z = 50; f[x_] := f[x] = Sum[Floor[(6/5)*(k + 1)] x^k, {k, 0, z}]; f[x]
CoefficientList[Series[1/f[x], {x, 0, z}], x]
LinearRecurrence[{-1, -1, -1, -2}, {1, -2, 0, -1, 3, -3}, 50] (* Harvey P. Dale, Mar 11 2024 *)
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Clark Kimberling, Dec 18 2016
STATUS
approved