OFFSET
0,4
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..600
N. J. A. Sloane, Transforms
FORMULA
a(n) ~ c * d^n / n^(3/2), where d = 3.382016466020272807429818743... (same as for A035080), c = 0.2780120087122189647675707... . - Vaclav Kotesovec, Sep 12 2014
MAPLE
g:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(b((i-1)$2), j)*g(n-i*j, i-1), j=0..n/i)))
end:
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(g(i$2), j)*b(n-i*j, i-1), j=0..n/i)))
end:
a:= n-> g(n, n):
seq(a(n), n=0..40); # Alois P. Heinz, May 20 2013
MATHEMATICA
g[n_, i_] := g[n, i] = If[n==0, 1, If[i<1, 0, Sum[Binomial[b[i-1, i-1], j]* g[n-i*j, i-1], {j, 0, n/i}]]];
b[n_, i_] := b[n, i] = If[n==0, 1, If[i<1, 0, Sum[Binomial[g[i, i], j]*b[n- i*j, i-1], {j, 0, n/i}]]];
a[n_] := g[n, n];
Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Feb 22 2017, after Alois P. Heinz *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Christian G. Bower, Nov 15 1998
STATUS
approved