A009712 Expansion of tan(tanh(sin(x))).

1, -1, -7, 391, -17263, 680239, 1450569, -7957325193, 2085950965153, -451440698199841, 87302333394141977, -12244874410272223257, -1227047210877649641679, 2438662572717698729224975

Offset

0,3

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Tan[Tanh[Sin[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jun 14 2016 *)

Crossrefs

Sequence in context: A184954 A185354 A222893 * A128793 A042527 A203588

Adjacent sequences: A009709 A009710 A009711 * A009713 A009714 A009715

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Prior Mathematica program replaced by Harvey P. Dale, Jun 14 2016

Status

approved