OFFSET
0,5
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..200
EXAMPLE
a(8) = 11: [1,1,3,3], [1,3,1,3], [1,3,3,1], [3,1,1,3], [3,1,3,1], [3,3,1,1], [1,1,1,1,4], [1,1,1,4,1], [1,1,4,1,1], [1,4,1,1,1], [4,1,1,1,1].
MAPLE
b:= proc(n, i, p) option remember; `if`(n=0, p!,
`if`(i<1, 0, expand(add(x^`if`(j=0, 0, i-j)*
b(n-i*j, i-1, p+j)/j!, j=0..n/i))))
end:
a:= n-> coeff(b(n$2, 0), x, 0):
seq(a(n), n=0..50);
MATHEMATICA
b[n_, i_, p_] := b[n, i, p] = If[n == 0, p!, If[i < 1, 0, Expand[Sum[x^If[j == 0, 0, i - j]*b[n - i*j, i - 1, p + j]/j!, {j, 0, n/i}]]]];
a[n_] := Coefficient[b[n, n, 0], x, 0];
Table[a[n], {n, 0, 50}] (* Jean-François Alcover, May 21 2018, translated from Maple *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, May 30 2014
STATUS
approved