A319755 - OEIS

A319755

Number of non-isomorphic intersecting set multipartitions (multisets of sets) of weight n.

1, 1, 2, 3, 6, 9, 19, 30, 60, 107, 212

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OFFSET

0,3

COMMENTS

A set multipartition is intersecting if no two parts are disjoint. The weight of a set multipartition is the sum of sizes of its parts. Weight is generally not the same as number of vertices.

LINKS

Table of n, a(n) for n=0..10.

EXAMPLE

Non-isomorphic representatives of the a(1) = 1 through a(5) = 9 set multipartitions:

1: {{1}}

2: {{1,2}}

{{1},{1}}

3: {{1,2,3}}

{{2},{1,2}}

{{1},{1},{1}}

4: {{1,2,3,4}}

{{3},{1,2,3}}

{{1,2},{1,2}}

{{1,3},{2,3}}

{{2},{2},{1,2}}

{{1},{1},{1},{1}}

5: {{1,2,3,4,5}}

{{4},{1,2,3,4}}

{{1,4},{2,3,4}}

{{2,3},{1,2,3}}

{{2},{1,2},{1,2}}

{{3},{3},{1,2,3}}

{{3},{1,3},{2,3}}

{{2},{2},{2},{1,2}}

{{1},{1},{1},{1},{1}}

CROSSREFS

Cf. A007716, A049311, A283877, A305854, A306006, A316980, A319616.

Cf. A319748, A319752, A319759, A319760, A319765, A319779, A319787, A319789.

Sequence in context: A011962 A060172 A193196 * A309807 A003243 A320160

Adjacent sequences: A319752 A319753 A319754 * A319756 A319757 A319758

KEYWORD

nonn,more

AUTHOR

Gus Wiseman, Sep 27 2018

STATUS

approved