A009241 Expansion of e.g.f.: exp(tan(tanh(x))).

1, 1, 1, 1, 1, -7, -47, -55, 449, 2897, 18209, 5105, -1441087, -7252983, 41192817, 341550201, 2660018305, 43255573537, -460752070079, -11238852308639, 21450325749889, 963068748879257, 1057483104728337, 153386988236833449

Offset

0,6

Links

Table of n, a(n) for n=0..23.

Mathematica

With[{nn=30}, CoefficientList[Series[Exp[Tan[Tanh[x]]], {x, 0, nn}], x] Range[ 0, nn]!] (* Harvey P. Dale, Apr 05 2022 *)

Crossrefs

Sequence in context: A068640 A089725 A086040 * A263920 A124837 A122731

Adjacent sequences: A009238 A009239 A009240 * A009242 A009243 A009244

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Definition clarified and prior Mathematica program replaced by Harvey P. Dale, Apr 05 2022

Status

approved