A276926 Number of ordered set partitions of [n] with at most six elements per block.

1, 1, 3, 13, 75, 541, 4683, 47292, 545818, 7086954, 102241902, 1622523210, 28089336198, 526810157874, 10640241569958, 230256584914356, 5314976561846952, 130352566702702344, 3385021286975255928, 92786398312428612792, 2677217312112863784264

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..6} x^i/i!).

Maple

a:= proc(n) option remember; `if`(n=0, 1, add(
       a(n-i)*binomial(n, i), i=1..min(n, 6)))
    end:
seq(a(n), n=0..25);

Mathematica

max = 25; CoefficientList[1/(1-Sum[x^i/i!, {i, 1, 6}]) + O[x]^(max+1), x]* Range[0, max]! (* Jean-François Alcover, May 24 2018 *)

Crossrefs

Column k=6 of A276921.

Cf. A148092.

Sequence in context: A276925 A343789 A276896 * A343790 A276897 A276927

Adjacent sequences: A276923 A276924 A276925 * A276927 A276928 A276929

Keyword

nonn

Author

Alois P. Heinz, Sep 22 2016

Status

approved