A012036 tan(sin(arcsinh(x)))=x-4/5!*x^5+32/7!*x^7+80/9!*x^9-34048/11!*x^11...

1, 0, -4, 32, 80, -34048, 5048512, -984048128, 246504417536, -76892124225536, 29350173573487616, -13506119868179701760, 7388967312556159062016, -4745632815309786449379328, 3538391474251613805070172160

Offset: 0

Author

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

Keywords

• sign

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..200

Programs

Mathematica

With[{nn=30},Take[CoefficientList[Series[Tan[Sin[ArcSinh[x]]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* Harvey P. Dale, May 19 2014 *)

Formula

a(n) ~ (-1)^n * c * (2*n)! / sqrt(n), where c = 0.05565047582054219883411112937... . - Vaclav Kotesovec, Feb 03 2015