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 A318402 Number of sets of nonempty sets whose multiset union is a strongly normal multiset of size n. 2
 1, 2, 6, 20, 74, 311, 1401, 6913, 36376 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A multiset is strongly normal if it spans an initial interval of positive integers with weakly decreasing multiplicities. LINKS EXAMPLE The a(4) = 20 sets of sets:   {{1,2,3,4}}   {{1},{1,2,3}}   {{1},{2,3,4}}   {{2},{1,3,4}}   {{3},{1,2,4}}   {{4},{1,2,3}}   {{1,2},{1,3}}   {{1,2},{3,4}}   {{1,3},{2,4}}   {{1,4},{2,3}}   {{1},{2},{1,2}}   {{1},{2},{1,3}}   {{1},{2},{3,4}}   {{1},{3},{1,2}}   {{1},{3},{2,4}}   {{1},{4},{2,3}}   {{2},{3},{1,4}}   {{2},{4},{1,3}}   {{3},{4},{1,2}}   {{1},{2},{3},{4}} CROSSREFS Cf. A007716, A049311, A050326, A116540, A283877, A292432, A292444, A318361, A318369, A318370. Sequence in context: A150158 A034010 A135588 * A293492 A150159 A150160 Adjacent sequences:  A318399 A318400 A318401 * A318403 A318404 A318405 KEYWORD nonn,more AUTHOR Gus Wiseman, Aug 25 2018 STATUS approved

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Last modified May 26 15:27 EDT 2020. Contains 334626 sequences. (Running on oeis4.)