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A321390 Third Moebius transform of A007716. Number of non-isomorphic aperiodic multiset partitions of weight n whose parts have relatively prime periods and whose dual is also an aperiodic multiset partition. 5
1, 1, 1, 7, 24, 88, 265, 907, 2929, 9918, 33931, 119366, 428314, 1574221, 5913415, 22699536, 88994103, 356058537, 1453049451, 6044132791, 25612496016, 110503624870, 485160989937, 2166488899639, 9835208617114, 45370059225048 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
The Moebius transform c of a sequence b is c(n) = Sum_{d|n} mu(d) * b(n/d).
Also the number of nonnegative integer matrices with sum of entries equal to n and no zero rows or columns where the multiset of rows and the multiset of columns are both aperiodic and the nonzero entries are relatively prime, up to row and column permutations.
A multiset is aperiodic if its multiplicities are relatively prime. The period of a multiset is the GCD of its multiplicities.
The dual of a multiset partition has, for each vertex, one part consisting of the indices (or positions) of the parts containing that vertex, counted with multiplicity. For example, the dual of {{1,2},{2,2}} is {{1},{1,2,2}}.
The weight of a multiset partition is the sum of sizes of its parts. Weight is generally not the same as number of vertices.
LINKS
EXAMPLE
Non-isomorphic representatives of the a(1) = 1 through a(4) = 24 multiset partitions:
{{1}} {{1},{2}} {{1,2,2}} {{1,2,2,2}}
{{1},{1,1}} {{1,2,3,3}}
{{1},{2,2}} {{1},{1,1,1}}
{{1},{2,3}} {{1},{1,2,2}}
{{2},{1,2}} {{1},{2,2,2}}
{{1},{2},{2}} {{1,2},{2,2}}
{{1},{2},{3}} {{1},{2,3,3}}
{{1,2},{3,3}}
{{1},{2,3,4}}
{{1,3},{2,3}}
{{2},{1,2,2}}
{{3},{1,2,3}}
{{1},{1},{1,1}}
{{1},{1},{2,2}}
{{1},{1},{2,3}}
{{1},{2},{1,2}}
{{1},{2},{2,2}}
{{1},{2},{3,3}}
{{1},{2},{3,4}}
{{1},{3},{2,3}}
{{2},{2},{1,2}}
{{1},{2},{2},{2}}
{{1},{2},{3},{3}}
{{1},{2},{3},{4}}
CROSSREFS
Sequence in context: A196349 A196352 A050191 * A283457 A129797 A188120
KEYWORD
nonn
AUTHOR
Gus Wiseman, Nov 08 2018
STATUS
approved

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Last modified April 19 09:23 EDT 2024. Contains 371782 sequences. (Running on oeis4.)