OFFSET
0,4
COMMENTS
The e.g.f. is a disguised form of the algebraic function (x+sqrt(1+x^2))/(1+x). - Peter Bala, Apr 22 2012
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..200
FORMULA
a(n) ~ n! * (-1)^n * (sqrt(2)-1). - Vaclav Kotesovec, Nov 01 2013
MATHEMATICA
CoefficientList[Series[Exp[ArcSinh[x]-Log[x+1]], {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Nov 01 2013 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved