OFFSET
0,4
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
EXAMPLE
-(1/2!)*x^2 + (4/3!)*x^3 - (6/4!)*x^4 + (8/5!)*x^5 - ...
MATHEMATICA
Range[0, 25]! CoefficientList[Series[ArcTanh[Log[x + 1] - Tanh[x]], {x, 0, 25}], x] (* Vincenzo Librandi, Aug 03 2018 *)
PROG
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(1+Argtanh(Log(x+1) - Tanh(x)))); [0] cat [Factorial(n-1)*b[n]: n in [2..m]]; // Vincenzo Librandi, Aug 03 2018
CROSSREFS
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 03 2018
STATUS
approved