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A330664 Number of non-isomorphic balanced reduced multisystems of maximum depth whose degrees (atom multiplicities) are the weakly decreasing prime indices of n. 7
1, 1, 1, 1, 1, 2, 2, 1, 4, 5, 5, 7, 16, 16, 27, 2, 61, 33, 272, 27, 123, 61, 1385, 27, 78, 272, 95, 123, 7936, 362 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
A balanced reduced multisystem is either a finite multiset, or a multiset partition with at least two parts, not all of which are singletons, of a balanced reduced multisystem.
A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798. A multiset whose multiplicities are the prime indices of n (such as row n of A305936) is generally not the same as the multiset of prime indices of n. For example, the prime indices of 12 are {1,1,2}, while a multiset whose multiplicities are {1,1,2} is {1,1,2,3}.
LINKS
FORMULA
For n > 1, a(2^n) = a(prime(n)) = A000111(n - 1).
EXAMPLE
Non-isomorphic representatives of the a(n) multisystems for n = 2, 3, 6, 9, 10, 12 (commas and outer brackets elided):
1 11 {1}{12} {{1}}{{1}{22}} {{1}}{{1}{12}} {{1}}{{1}{23}}
{2}{11} {{11}}{{2}{2}} {{11}}{{1}{2}} {{11}}{{2}{3}}
{{1}}{{2}{12}} {{1}}{{2}{11}} {{1}}{{2}{13}}
{{12}}{{1}{2}} {{12}}{{1}{1}} {{12}}{{1}{3}}
{{2}}{{1}{11}} {{2}}{{1}{13}}
{{2}}{{3}{11}}
{{23}}{{1}{1}}
CROSSREFS
The non-maximal version is A330666.
The case of constant or strict atoms is A000111.
Labeled versions are A330728, A330665 (prime indices), and A330675 (strongly normal).
Non-isomorphic multiset partitions whose degrees are the prime indices of n are A318285.
Sequence in context: A113547 A218580 A259697 * A330843 A115313 A048942
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Dec 28 2019
STATUS
approved

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Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)