OFFSET
0,6
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..450
EXAMPLE
E.g.f. = 1 + x + x^2/2! + x^3/3! + x^4/4! + 9*x^5/5! + ...
MAPLE
seq(coeff(series(factorial(n)*exp(arctanh(arctan(x))), x, n+1), x, n), n = 0 .. 25); # Muniru A Asiru, Oct 29 2018
MATHEMATICA
With[{nn=30}, CoefficientList[Series[Exp[ArcTanh[ArcTan[x]]], {x, 0, nn}], x] Range[0, nn]!] (* Ray Chandler, Nov 28 2016 *)
PROG
(PARI) x='x+O('x^30); Vec(serlaplace(exp(atanh(atan(x))))) \\ G. C. Greubel, Oct 28 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( Exp(Argtanh(Arctan(x))) )); [Factorial(n-1)*b[n]: n in [1..m-1]]; // G. C. Greubel, Oct 28 2018
CROSSREFS
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved