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A319560
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Number of non-isomorphic strict T_0 multiset partitions of weight n.
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17
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1, 1, 2, 6, 15, 40, 121, 353, 1107, 3550, 11818
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OFFSET
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0,3
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COMMENTS
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In a multiset partition, two vertices are equivalent if in every block the multiplicity of the first is equal to the multiplicity of the second. The T_0 condition means that there are no equivalent vertices.
The weight of a multiset partition is the sum of sizes of its parts. Weight is generally not the same as number of vertices.
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LINKS
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EXAMPLE
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Non-isomorphic representatives of the a(1) = 1 through a(4) = 15 multiset partitions:
1: {{1}}
2: {{1,1}}
{1},{2}}
3: {{1,1,1}}
{{1,2,2}}
{{1},{1,1}}
{{1},{2,2}}
{{2},{1,2}}
{{1},{2},{3}}
4: {{1,1,1,1}}
{{1,2,2,2}}
{{1},{1,1,1}}
{{1},{1,2,2}}
{{1},{2,2,2}}
{{1},{2,3,3}}
{{2},{1,2,2}}
{{1,1},{2,2}}
{{1,2},{2,2}}
{{1,3},{2,3}}
{{1},{2},{1,2}}
{{1},{2},{2,2}}
{{1},{2},{3,3}}
{{1},{3},{2,3}}
{{1},{2},{3},{4}}
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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