OFFSET
0,4
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..450
EXAMPLE
E.g.f. = 1 - x^2/2! - 3*x^3/3! - 6*x^4/4! + 30*x^5/5! - ...
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Sech[Exp[x]Log[x+1]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jan 21 2013 *)
PROG
(PARI) x='x+O('x^30); Vec(serlaplace(1/cosh(exp(x)*log(x+1)))) \\ G. C. Greubel, Oct 28 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( 1/Cosh(Exp(x)*Log(x+1)) )); [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)
EXTENSIONS
Definition clarified by Harvey P. Dale, Jan 21 2013
STATUS
approved