OFFSET
0,3
COMMENTS
Inverse Lah transform of A000312.
LINKS
N. J. A. Sloane, Transforms
FORMULA
a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n-1,k-1)*k^k*n!/k!.
a(n) ~ n^n * (exp(1) - 1)^(n - 1/2) / exp(n - 1/2). - Vaclav Kotesovec, Aug 18 2018
MAPLE
a:=series(1/(1+LambertW(-x/(1+x))), x=0, 23): seq(n!*coeff(a, x, n), n=0..22); # Paolo P. Lava, Mar 26 2019
MATHEMATICA
nmax = 22; CoefficientList[Series[1/(1 + LambertW[-x/(1 + x)]), {x, 0, nmax}], x] Range[0, nmax]!
Join[{1}, Table[Sum[(-1)^(n - k) Binomial[n - 1, k - 1] k^k n!/k!, {k, n}], {n, 22}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Aug 18 2018
STATUS
approved