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 A317752 Number of multiset partitions of normal multisets of size n such that the blocks have empty intersection. 21
 0, 1, 8, 49, 305, 1984, 13686, 100124 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS A multiset is normal if it spans an initial interval of positive integers. LINKS EXAMPLE The a(3) = 8 multiset partitions with empty intersection:   {{2},{1,1}}   {{1},{2,2}}   {{1},{2,3}}   {{2},{1,3}}   {{3},{1,2}}   {{1},{1},{2}}   {{1},{2},{2}}   {{1},{2},{3}} MATHEMATICA sps[{}]:={{}}; sps[set:{i_, ___}]:=Join@@Function[s, Prepend[#, s]&/@sps[Complement[set, s]]]/@Cases[Subsets[set], {i, ___}]; mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]]; allnorm[n_]:=Function[s, Array[Count[s, y_/; y<=#]+1&, n]]/@Subsets[Range[n-1]+1]; Table[Length[Join@@Table[Select[mps[m], Intersection@@#=={}&], {m, allnorm[n]}]], {n, 6}] CROSSREFS Cf. A007716, A255903, A255906, A317073, A281116, A317077, A317532, A317533. Cf. A317748, A317751, A317755, A317757, A317776. Sequence in context: A037539 A037483 A188708 * A273497 A024106 A176626 Adjacent sequences:  A317749 A317750 A317751 * A317753 A317754 A317755 KEYWORD nonn,more AUTHOR Gus Wiseman, Aug 06 2018 STATUS approved

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Last modified October 18 13:59 EDT 2019. Contains 328161 sequences. (Running on oeis4.)