A009660 Expansion of tan(sin(tanh(x))).

1, -1, -7, 447, -19471, 612127, 37384233, -15027743521, 3099354722529, -493631745542209, 34013990822822489, 22054949830590352511, -16492842082602835130159, 7774163613641172354365407

Offset

0,3

Links

Table of n, a(n) for n=0..13.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Tan[Sin[Tanh[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jan 18 2019 *)

Crossrefs

Sequence in context: A269555 A027876 A158599 * A024097 A203060 A261479

Adjacent sequences: A009657 A009658 A009659 * A009661 A009662 A009663

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, Jan 18 2019

Status

approved