A009508 Expansion of sin(tan(x))*x.

0, 2, 4, -18, -2200, -150150, -11618004, -1078005082, -118928710576, -15184771406478, -2148536703814700, -309605570133329954, -34193099991177752904, 4268254817856544829418, 6637048590856623019431932

Offset

0,2

Links

Table of n, a(n) for n=0..14.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Sin[Tan[x]]x, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, May 27 2022 *)

Crossrefs

Sequence in context: A318531 A009667 A356123 * A275000 A290595 A009418

Adjacent sequences: A009505 A009506 A009507 * A009509 A009510 A009511

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, May 27 2022

Status

approved