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Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 6/5.
5

%I #15 Mar 11 2024 19:25:25

%S 1,-2,1,0,-1,3,-3,1,1,-5,9,-7,1,7,-19,25,-15,-5,33,-63,65,-25,-43,129,

%T -191,155,-7,-215,449,-537,317,201,-879,1435,-1391,433,1281,-3193,

%U 4261,-3215,-415,5755,-10647,11737,-6015,-6585,22157,-33031,29489,-5445

%N Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 6/5.

%H Clark Kimberling, <a href="/A279778/b279778.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (-1,-1,-1,-2).

%F G.f.: 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = 6/5.

%F G.f.: (1 - x) (1 - x^5)/(1 + x + x^2 + x^3 + 2 x^4).

%t z = 50; f[x_] := f[x] = Sum[Floor[(6/5)*(k + 1)] x^k, {k, 0, z}]; f[x]

%t CoefficientList[Series[1/f[x], {x, 0, z}], x]

%t LinearRecurrence[{-1,-1,-1,-2},{1,-2,0,-1,3,-3},50] (* _Harvey P. Dale_, Mar 11 2024 *)

%Y Cf. A279634, A279779, A279780, A279781.

%K sign,easy

%O 0,2

%A _Clark Kimberling_, Dec 18 2016