OFFSET
0,3
COMMENTS
Lah transform of A000587 (complementary Bell numbers).
FORMULA
a(n) = Sum_{k=0..n} binomial(n-1,k-1)*A000587(k)*n!/k!.
MATHEMATICA
nmax = 22; CoefficientList[Series[Exp[1 - Exp[x/(1 - x)]], {x, 0, nmax}], x] Range[0, nmax]!
a[n_] := a[n] = Sum[Binomial[n - 1, k - 1] BellB[k, -1] n!/k!, {k, 0, n}]; Table[a[n], {n, 0, 22}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Jun 03 2019
STATUS
approved