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

%I #9 Mar 30 2017 04:30:58

%S 1,-2,1,0,-1,3,-3,1,0,-1,3,-3,2,-4,5,-1,-3,7,-14,15,-6,-2,8,-18,22,

%T -17,18,-17,-4,29,-47,69,-71,28,24,-63,110,-136,109,-76,36,76,-213,

%U 296,-348,316,-92,-215,455,-664,767,-595,270,102,-697,1383,-1745,1742

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

%H Clark Kimberling, <a href="/A279594/b279594.txt">Table of n, a(n) for n = 0..1000</a>

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

%t z = 30; r = Sqrt[6]/2;

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

%t CoefficientList[Series[1/f[x], {x, 0, 2*z}], x]

%o (PARI) r = sqrt(6)/2;

%o Vec(1/sum(k=0, 60, floor(r*(k + 1))*x^k) + O(x^61)) \\ _Indranil Ghosh_, Mar 30 2017

%Y Cf. A279607.

%K sign,easy

%O 0,2

%A _Clark Kimberling_, Dec 16 2016