A009353 Expansion of log(1+sinh(x))*exp(x).

0, 1, 1, 3, 0, 20, -85, 637, -5096, 46944, -484401, 5544341, -69697672, 954728788, -14155260197, 225856326165, -3858874322928, 70293211672352, -1359957800892673, 27849583539856909, -601828107666316064

Offset: 0

Author

R. H. Hardin

Keywords

• sign
• easy

Programs

Mathematica

Log[ 1+Sinh[ x ] ]*Exp[ x ]
CoefficientList[Series[E^x*Log[1 + Sinh[x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)

Formula

a(n) ~ (n-1)! * (-1)^(n+1) * (sqrt(2)-1) / (log(1+sqrt(2)))^n. - Vaclav Kotesovec, Jan 23 2015

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997