A292444 Number of non-isomorphic finite multisets that cannot be expressed as the multiset-union of a set of sets.

0, 1, 1, 2, 3, 5, 6, 9, 12, 17, 22

Offset

1,4

Comments

Non-isomorphic finite multisets correspond to integer partitions. For example, the partition (3221) corresponds to the multiset {1,1,1,2,2,3,3,4}.

Problem: Is this sequence equal to A258939 or to A035948?

Links

Table of n, a(n) for n=1..11.

Example

Representatives of the a(7) = 6 multisets are: {1,1,1,1,1,1,1}, {1,1,1,1,1,1,2}, {1,1,1,1,1,2,2}, {1,1,1,1,1,2,3}, {1,1,1,1,2,2,2}, {1,1,1,1,2,2,3}.

Crossrefs

Cf. A049311, A089259, A116540, A283877, A292432.

Sequence in context: A046966 A225973 A329165 * A035948 A258939 A244747

Adjacent sequences: A292441 A292442 A292443 * A292445 A292446 A292447

Keyword

nonn,more

Author

Gus Wiseman, Oct 02 2017

Status

approved