OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..100
MAPLE
A:= proc(n) option remember; if n=0 then 1 else unapply (convert (series (exp (x* A(n-1)(exp(x)-1)), x, n+1), polynom), x) fi end; a:= n-> coeff (A(n)(x), x, n)*n!: seq (a(n), n=0..20);
MATHEMATICA
A[n_] := A[n] = If[n == 0, 1, Normal[Series[Exp[x*A[n-1][Exp[x]-1]], {x, 0, n+1}]] /. x -> #]&; a[n_] := Coefficient[A[n][x], x, n]*n!; Table[a[n], {n, 0, 20}] (* Jean-François Alcover, Feb 14 2014, after Maple *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Aug 24 2008
STATUS
approved