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%I #5 Sep 26 2018 16:26:36
%S 1,1,3,4,10,14,48,95,305,822,2615
%N Number of non-isomorphic connected antichains of multisets of weight n.
%C In an antichain, no part is a proper submultiset of any other. The weight of an antichain is the sum of sizes of its parts. Weight is generally not the same as number of vertices. Connected antichains are also called clutters.
%H Goran Kilibarda and Vladeta Jovovic, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL7/Kilibarda/kili2.pdf">Antichains of Multisets</a>, Journal of Integer Sequences, Vol. 7 (2004).
%e Non-isomorphic representatives of the a(1) = 1 through a(4) = 10 connected antichains:
%e 1: {{1}}
%e 2: {{1,1}}
%e {{1,2}}
%e {{1},{1}}
%e 3: {{1,1,1}}
%e {{1,2,2}}
%e {{1,2,3}}
%e {{1},{1},{1}}
%e 4: {{1,1,1,1}}
%e {{1,1,2,2}}
%e {{1,2,2,2}}
%e {{1,2,3,3}}
%e {{1,2,3,4}}
%e {{1,1},{1,1}}
%e {{1,2},{1,2}}
%e {{1,2},{2,2}}
%e {{1,3},{2,3}}
%e {{1},{1},{1},{1}}
%Y Cf. A001055, A001970, A007716, A007718, A056156, A096827, A253249, A285573, A293994, A318099, A319557, A319616-A319646, A319721.
%K nonn,more
%O 0,3
%A _Gus Wiseman_, Sep 26 2018
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