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A009553 Expansion of e.g.f. sin(x)/cos(sin(x)) (odd powers only). 1
1, 2, -4, -176, -1712, 66912, 4737344, 53926656, -18559434496, -1869838374400, 35429689535488, 36301265658269696, 4137398544580202496, -569857298193726644224, -297369786811582548131840 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..248

MATHEMATICA

With[{nmax = 50}, CoefficientList[Series[Sin[x]/Cos[Sin[x]], {x, 0, nmax}], x]*Range[0, nmax - 1]!][[2 ;; ;; 2]] (* G. C. Greubel, Jan 20 2018 *)

PROG

(PARI) x='x+O('x^50); v=Vec(serlaplace(sin(x)/cos(sin(x)))); vector((#v-1)\2 , n, v[2*n-1]) // G. C. Greubel, Jan 20 2018

CROSSREFS

Sequence in context: A023171 A018595 A260900 * A012371 A009815 A012693

Adjacent sequences:  A009550 A009551 A009552 * A009554 A009555 A009556

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified February 17 12:32 EST 2020. Contains 331996 sequences. (Running on oeis4.)