A141623 E.g.f. satisfies: A(x) = exp(x*A(exp(x)-1)).

1, 1, 3, 19, 189, 2646, 48763, 1131586, 32049993, 1082499355, 42824201581, 1956135246121, 101971684168885, 6007537986240493, 396692981028462147, 29151125494423827526, 2369159815571293228865, 211779737665939491669492

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

Sequence in context: A367180 A326553 A052888 * A229234 A090354 A119394

Adjacent sequences: A141620 A141621 A141622 * A141624 A141625 A141626

Keyword

nonn

Author

Alois P. Heinz, Aug 24 2008

Status

approved