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A009509
Expansion of sin(tan(x))/cos(x).
0
1, 4, 32, 264, -9216, -1548032, -190744448, -25395878400, -3862395551744, -674521189158912, -133945803441307648, -29717777068093669376, -7172117320170458939392, -1797012698406108143681536
OFFSET
0,2
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Sin[Tan[x]]/Cos[x], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Dec 23 2017 *)
CROSSREFS
Sequence in context: A013731 A092811 A363440 * A036725 A065089 A113329
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
Prior Mathematica program replaced by Harvey P. Dale, Dec 23 2017
STATUS
approved