A239914 Total number of preferential arrangements of 1, 2, ..., n things.

1, 4, 17, 92, 633, 5316, 52609, 598444, 7685705, 109933268, 1732565841, 29824133436, 556682481817, 11198025452260, 241481216430113, 5557135898411468, 135927902927547369, 3521462566184392692, 96323049885512803825, 2774010846129897006940

Offset

1,2

Comments

Although A217389 = a(n)+1 already exists, it is this sequence that one really needs.

Links

Table of n, a(n) for n=1..20.

Formula

a(n) = Sum_{k=1..n} A000670(k).

Crossrefs

Cf. A000670, A217389.

Sequence in context: A316084 A112354 A020011 * A323664 A067084 A123750

Adjacent sequences: A239911 A239912 A239913 * A239915 A239916 A239917

Keyword

nonn

Author

N. J. A. Sloane, Apr 12 2014

Status

approved