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%I #4 Sep 26 2018 16:26:44
%S 1,1,4,8,24,50,148,349,1014,2717,8114
%N Number of non-isomorphic 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.
%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(3) = 8 antichains:
%e 1: {{1}}
%e 2: {{1,1}}
%e {{1,2}}
%e {{1},{1}}
%e {{1},{2}}
%e 3: {{1,1,1}}
%e {{1,2,2}}
%e {{1,2,3}}
%e {{1},{2,2}}
%e {{1},{2,3}}
%e {{1},{1},{1}}
%e {{1},{2},{2}}
%e {{1},{2},{3}}
%Y Cf. A001055, A001970, A007716, A096827, A253249, A285572, A285573, A293993, A318099, A319616-A319646, A319719.
%K nonn,more
%O 0,3
%A _Gus Wiseman_, Sep 26 2018
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