OFFSET
1,5
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..100
N. J. A. Sloane, Transforms
MATHEMATICA
a[n:0|1] := n; a[n_] := a[n] = Sum[m a[m] a[n-k*m], {m, n-1}, {k, (n-1)/m}]/(n-1); length = 20; Range[length]! InverseSeries[Sum[a[n] x^n/n!, {n, 0, length}] + O[x]^(length+1)][[3]] (* Vladimir Reshetnikov, Nov 06 2015 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Christian G. Bower, Nov 15 1999
STATUS
approved