OFFSET
0,4
EXAMPLE
x + 2/3!*x^3 - 4/4!*x^4 + 20/5!*x^5 - 120/6!*x^6 ...
PROG
(PARI) x = 'x + O('x^30); concat(0, Vec(serlaplace(asin(exp(x) - 1/cos(x))))) \\ Michel Marcus, Aug 06 2018
CROSSREFS
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
a(0)=0 inserted and title improved by Sean A. Irvine, Aug 05 2018
STATUS
approved