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A279592 Coefficients in the expansion of 1/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = Pi/2. 1
1, -3, 5, -9, 18, -36, 72, -144, 287, -570, 1132, -2250, 4473, -8892, 17676, -35137, 69847, -138845, 276002, -548649, 1090629, -2168001, 4309649, -8566912, 17029689, -33852374, 67293256, -133768530, 265911039, -528589801, 1050754338, -2088736250, 4152082903 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Clark Kimberling, Table of n, a(n) for n = 0..1000

FORMULA

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

MATHEMATICA

z = 30; r = Pi/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]

PROG

(PARI) r = Pi/2;

Vec(1/sum(k=0, 70, floor(r*(k + 1))*x^k) + O(x^71)) \\ Indranil Ghosh, Mar 30 2017

CROSSREFS

Cf. A279607.

Sequence in context: A288230 A289262 A288231 * A288229 A293332 A288135

Adjacent sequences:  A279589 A279590 A279591 * A279593 A279594 A279595

KEYWORD

sign,easy

AUTHOR

Clark Kimberling, Dec 16 2016

STATUS

approved

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Last modified September 19 18:37 EDT 2020. Contains 337181 sequences. (Running on oeis4.)