OFFSET
1,1
FORMULA
a(n) ~ sqrt(s/(3-2*s)) * n^(n-1) / (exp(n) * r^n), where s = 0.6693241011832267063... is the root of the equation (2-1/s)*(2+exp(s)) = 2, and r = s*exp(-s)/(2+exp(s)) = 0.08670317777647875508... - Vaclav Kotesovec, Jan 26 2014
MATHEMATICA
Rest[CoefficientList[InverseSeries[Series[(x/(E^x*(2+E^x))), {x, 0, 20}], x], x]*Range[0, 20]!]
Table[Sum[2^j*(2*n-j)^(n-1)*Binomial[n, j], {j, 0, n}], {n, 1, 20}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Jan 26 2014
STATUS
approved