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 A321681 Number of non-isomorphic weight-n connected strict antichains of multisets with multiset density -1. 2
 1, 1, 2, 3, 7, 13, 35, 77, 205, 517, 1399 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The multiset density of a multiset partition is the sum of the numbers of distinct vertices in each part minus the number of parts minus the number of vertices. The weight of a multiset partition is the sum of sizes of its parts. Weight is generally not the same as number of vertices. LINKS Table of n, a(n) for n=0..10. EXAMPLE Non-isomorphic representatives of the a(1) = 1 through a(5) = 13 trees: {{1}} {{1,1}} {{1,1,1}} {{1,1,1,1}} {{1,1,1,1,1}} {{1,2}} {{1,2,2}} {{1,1,2,2}} {{1,1,2,2,2}} {{1,2,3}} {{1,2,2,2}} {{1,2,2,2,2}} {{1,2,3,3}} {{1,2,2,3,3}} {{1,2,3,4}} {{1,2,3,3,3}} {{1,2},{2,2}} {{1,2,3,4,4}} {{1,3},{2,3}} {{1,2,3,4,5}} {{1,1},{1,2,2}} {{1,2},{2,2,2}} {{1,2},{2,3,3}} {{1,3},{2,3,3}} {{1,4},{2,3,4}} {{3,3},{1,2,3}} CROSSREFS Cf. A006126, A007718, A056156, A096827, A285572, A293993, A293994, A305052, A319557, A319565, A319719, A319721, A321585, A321680. Sequence in context: A129859 A280765 A056953 * A045611 A006840 A123408 Adjacent sequences: A321678 A321679 A321680 * A321682 A321683 A321684 KEYWORD nonn,more AUTHOR Gus Wiseman, Nov 16 2018 STATUS approved

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Last modified June 3 22:46 EDT 2023. Contains 363116 sequences. (Running on oeis4.)