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A303546
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Number of non-isomorphic aperiodic multiset partitions of weight n.
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28
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1, 3, 9, 29, 90, 285, 909, 2984, 9935, 34113, 119368, 428923, 1574223, 5915235, 22699730, 89000042, 356058539, 1453069854, 6044132793, 25612564200, 110503626702, 485161228675, 2166488899641, 9835209480533, 45370059225227
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OFFSET
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1,2
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COMMENTS
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A multiset is aperiodic if its multiplicities are relatively prime. For this sequence neither the parts nor their multiset union are required to be aperiodic, only the multiset of parts.
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LINKS
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FORMULA
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a(n) = Sum_{d|n} mu(d) * A007716(n/d).
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EXAMPLE
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Non-isomorphic representatives of the a(3) = 9 aperiodic multiset partitions are:
{{1,1,1}}, {{1,2,2}}, {{1,2,3}},
{{1},{1,1}}, {{1},{2,2}}, {{1},{2,3}}, {{2},{1,2}},
{{1},{2},{2}}, {{1},{2},{3}}.
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CROSSREFS
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Cf. A000740, A000837, A001055, A007716, A007916, A049311, A100953, A255906, A269134, A275024, A293993, A301700, A303386, A303431, A303547.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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