A013242 Expansion of e.g.f. arctanh(log(x+1) - tan(x)).

0, 0, -1, 0, -6, 8, -150, 448, -7560, 38432, -650160, 4827328, -85887648, 855019904, -16230758544, 204362847232, -4163699379840, 63548399361536, -1392682970270592, 24960951809133568, -588583828329908480

Offset

0,5

Links

Table of n, a(n) for n=0..20.

Example

-1/2!*x^2 - 6/4!*x^4 + 8/5!*x^5 - 150/6!*x^6 ...

Mathematica

With[{nn=20}, Drop[CoefficientList[Series[ArcTanh[Log[x+1]-Tan[x]], {x, 0, nn}], x] Range[0, nn]!, 2]] (* Harvey P. Dale, Aug 17 2016 *)

Crossrefs

Sequence in context: A257869 A201387 A013236 * A169971 A295429 A267165

Adjacent sequences: A013239 A013240 A013241 * A013243 A013244 A013245

Keyword

sign

Author

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

Extensions

a(0)=a(1)=0 inserted and title improved by Sean A. Irvine, Aug 02 2018

Status

approved