A374573 Number of sets of nonempty subsets of [n] where each element appears in at most n subsets.

1, 2, 8, 109, 11087, 15312665, 422059040480, 312210595377427422, 7962423724145466121172404, 8668986293188852191645897272339367

Offset

0,2

Links

Table of n, a(n) for n=0..9.

Formula

a(n) = A330964(n,n).

Example

a(0) = 1: {}.
a(1) = 2: {}, {{1}}.
a(2) = 8: {}, {{1}}, {{2}}, {{1,2}}, {{1},{2}}, {{1},{1,2}}, {{2},{1,2}}, {{1},{2},{1,2}}.

Crossrefs

Main diagonal of A330964.

Sequence in context: A374875 A322643 A178171 * A132523 A012554 A362727

Adjacent sequences: A374570 A374571 A374572 * A374574 A374575 A374576

Keyword

nonn,more

Author

Alois P. Heinz, Jul 11 2024

Status

approved