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A330233
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Least MM-numbers of multisets of multisets with a given number of distinct representatives (obtainable by vertex-permutations).
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11
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1, 35, 141, 1713, 28011, 355, 34567, 4045, 54849, 64615, 15265, 95363, 126841
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OFFSET
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1,2
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COMMENTS
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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. The multiset of multisets with MM-number n is formed by taking the multiset of prime indices of each part of the multiset of prime indices of n. For example, the prime indices of 78 are {1,2,6}, so the multiset of multisets with MM-number 78 is {{},{1},{1,2}}.
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LINKS
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EXAMPLE
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The sequence of terms together with their corresponding multisets of multisets begins:
1: {}
35: {{2},{1,1}}
141: {{1},{2,3}}
355: {{2},{1,1,3}}
1713: {{1},{2,3,4}}
4045: {{2},{1,1,3,4}}
15265: {{2},{1,4},{1,1,3}}
28011: {{1},{2,3,4,5}}
34567: {{1,2},{3,4,5}}
54849: {{1},{2,3},{4,5}}
64615: {{2},{1,1,3,4,5}}
95363: {{2,3},{1,1,4,5}}
126841: {{3},{1,2},{1,4,5}}
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MATHEMATICA
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primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
graprms[m_]:=Union[Table[Sort[Sort/@(m/.Apply[Rule, Table[{p[[i]], i}, {i, Length[p]}], {1}])], {p, Permutations[Union@@m]}]];
dv=Table[Length[graprms[primeMS/@primeMS[n]]], {n, 1000}];
Table[Position[dv, i][[1, 1]], {i, First/@Gather[dv]}]
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CROSSREFS
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Sorted positions of first appearances in A330098.
MM-numbers of achiral multisets of multisets are A330232.
MM-numbers of fully-chiral multisets of multisets are A330236.
Cf. A001055, A003238, A007716, A056239, A112798, A302242, A303975, A322847, A330103, A330223, A330227, A330231.
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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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