A012188 E.g.f. sinh(arctan(sin(x))) odd powers only.

1, -2, 16, -272, 256, 1758208, -549115904, 178127730688, -68157333438464, 31349506823815168, -17274394522483687424, 11298666083444901019648, -8681212227186028691062784, 7756335594110841587790512128

Offset

0,2

Comments

Previous name was: sinh(arctan(sin(x))) = x - 2/3!*x^3 + 16/5!*x^5 - 272/7!*x^7 + 256/9!*x^9 + ...

Links

G. C. Greubel, Table of n, a(n) for n = 0..219

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Sinh[ArcTan[Sin[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Nov 06 2013 *)

Prog

(PARI) x = 'x + O('x^40); select(x->x, Vec(serlaplace(sinh(atan(sin(x)))))) \\ Michel Marcus, Feb 05 2016

Crossrefs

Sequence in context: A283685 A197458 A050974 * A217816 A000182 A009764

Adjacent sequences: A012185 A012186 A012187 * A012189 A012190 A012191

Keyword

sign

Author

Patrick Demichel (patrick.demichel(AT)hp.com)

Extensions

New name from Michel Marcus, Feb 05 2016

Title corrected by Sean A. Irvine, Jul 11 2018

Status

approved