A012562 arctanh(sinh(x)*arctan(x)) = 2/2!*x^2 - 4/4!*x^4 + 350/6!*x^6 - 11240/8!*x^8 + ...

0, 2, -4, 350, -11240, 1703578, -193890860, 49492653366, -12321392081232, 4919573673167538, -2124948350723616724, 1246509899975408733326, -820629733751515166342200, 671843179144303883329974346, -622270861646882104886119580924

Offset

0,2

Links

Table of n, a(n) for n=0..14.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcTanh[Sinh[x]ArcTan[x]], {x, 0, nn}], x]Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Nov 16 2012 *)

Crossrefs

Sequence in context: A012613 A012618 A012557 * A263959 A216024 A247220

Adjacent sequences: A012559 A012560 A012561 * A012563 A012564 A012565

Keyword

sign

Author

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

Status

approved