A009816 tanh(sinh(x)*tan(x)) = 2/2!*x^2 + 12/4!*x^4 - 98/6!*x^6 - 16968/8!*x^8 - ...

0, 2, 12, -98, -16968, -1022758, 13538052, 18891204022, 3769346994672, 123100068974642, -253651389915077508, -122777845265771787698, -18798053944871656928088, 18504747132976573022229002

Offset

0,2

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Tanh[Tan[x]*Sinh[x]], {x, 0, nn}], x]Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Mar 26 2012 *)

Crossrefs

Sequence in context: A372154 A012548 A012550 * A227084 A064370 A138421

Adjacent sequences: A009813 A009814 A009815 * A009817 A009818 A009819

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved