A276927 Number of ordered set partitions of [n] with at most seven elements per block.

1, 1, 3, 13, 75, 541, 4683, 47293, 545834, 7087242, 102247182, 1622624850, 28091404902, 526854753282, 10641259374174, 230281144233426, 5315601950221992, 130369339178641992, 3385494089758915992, 92800379366660198376, 2677650178353887869704

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..424

Formula

E.g.f.: 1/(1-Sum_{i=1..7} x^i/i!).

Maple

a:= proc(n) option remember; `if`(n=0, 1, add(
       a(n-i)*binomial(n, i), i=1..min(n, 7)))
    end:
seq(a(n), n=0..25);

Mathematica

max = 25; CoefficientList[1/(1-Sum[x^i/i!, {i, 1, 7}]) + O[x]^(max+1), x]* Range[0, max]! (* Jean-François Alcover, May 24 2018 *)

Crossrefs

Column k=7 of A276921.

Cf. A229224.

Sequence in context: A276926 A343790 A276897 * A343791 A276898 A276928

Adjacent sequences: A276924 A276925 A276926 * A276928 A276929 A276930

Keyword

nonn

Author

Alois P. Heinz, Sep 22 2016

Status

approved