OFFSET
0,5
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..576
Wikipedia, Partition of a set
EXAMPLE
a(4) = 6: 432|1, 42|31, 42|3|1, 4|31|2, 4|3|21, 4|3|2|1.
MAPLE
b:= proc(n, m) option remember; `if`(n=0, 1, add(
`if`(j=n, 0, b(n-1, max(m, j))), j=1..m+1))
end:
a:= n-> b(n, 0):
seq(a(n), n=0..25);
MATHEMATICA
b[n_, m_] := b[n, m] = If[n == 0, 1, Sum[
If[j == n, 0, b[n-1, Max[m, j]]], {j, 1, m+1}]];
a[n_] := b[n, 0];
Table[a[n], {n, 0, 25}] (* Jean-François Alcover, May 16 2022, after Alois P. Heinz *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jan 09 2022
STATUS
approved