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 A293993 Number of unlabeled multiset antichains of weight n. 46
 1, 1, 3, 6, 16, 35, 98, 242, 690 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A multiset antichain is a finite set of finite nonempty multisets, none of which is a submultiset of any other. The weight of an antichain is the sum of cardinalities (counting multiplicity) of its elements. LINKS FORMULA Euler transform of A293994. EXAMPLE Non-isomorphic representatives of the a(4) = 16 antichains are: ((1111)), ((1112)), ((1122)), ((1123)), ((1234)), ((1)(234)), ((2)(111)), ((2)(113)), ((11)(12)), ((11)(22)), ((11)(23)), ((12)(13)), ((12)(34)), ((1)(2)(34)),((2)(3)(11)), ((1)(2)(3)(4)). CROSSREFS Cf. A007716, A285572, A293606, A293994. Sequence in context: A327736 A319752 A130095 * A072824 A089406 A027852 Adjacent sequences:  A293990 A293991 A293992 * A293994 A293995 A293996 KEYWORD nonn,more AUTHOR Gus Wiseman, Oct 21 2017 STATUS approved

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Last modified May 12 07:28 EDT 2021. Contains 343821 sequences. (Running on oeis4.)