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A303546 Number of non-isomorphic aperiodic multiset partitions of weight n. 28
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
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.
LINKS
FORMULA
a(n) = Sum_{d|n} mu(d) * A007716(n/d).
EXAMPLE
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}}.
CROSSREFS
Sequence in context: A220950 A123947 A262253 * A135142 A195624 A098589
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 26 2018
STATUS
approved

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Last modified May 13 09:31 EDT 2024. Contains 372504 sequences. (Running on oeis4.)