A012693 arctan(tanh(x)*sinh(x))=2/2!*x^2-4/4!*x^4-178/6!*x^6+5336/8!*x^8...

2, -4, -178, 5336, 363002, -51606124, -2970605818, 1739354509616, -3370162346638, -146251701849391444, 20841577570771860542, 24665031557633886866696, -10649944278498283837904278

Offset

0,1

Links

Table of n, a(n) for n=0..12.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcTan[Tanh[x]Sinh[x]], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 2}]] (* Harvey P. Dale, Nov 12 2014 *)

Crossrefs

Sequence in context: A009553 A012371 A009815 * A018608 A018611 A012369

Adjacent sequences: A012690 A012691 A012692 * A012694 A012695 A012696

Keyword

sign

Author

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

Status

approved