OFFSET
0,3
COMMENTS
A multiset partition is a finite multiset of finite nonempty multisets. It is a weak antichain if no part is a proper submultiset of any other.
EXAMPLE
Non-isomorphic representatives of the a(0) = 1 through a(5) = 11 multiset partitions:
{} {{1}} {{11}} {{111}} {{1111}} {{11111}}
{{12}} {{122}} {{1122}} {{11222}}
{{1}{1}} {{123}} {{1222}} {{12222}}
{{1}{1}{1}} {{1233}} {{12233}}
{{1234}} {{12333}}
{{11}{11}} {{12344}}
{{12}{12}} {{12345}}
{{12}{22}} {{11}{122}}
{{1}{1}{1}{1}} {{12}{222}}
{{33}{123}}
{{1}{1}{1}{1}{1}}
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Aug 18 2019
STATUS
approved