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Antichains in the set of subsets of a multiset

โœ Scribed by G.F Clements


Publisher
Elsevier Science
Year
1984
Tongue
English
Weight
946 KB
Volume
48
Category
Article
ISSN
0012-365X

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โœฆ Synopsis


A set F of distinct subsets x of a finite muhiset M (that is, a set with several different kinds of elements) is a c-antichain if for no c+l elements Xo, xl ..... x c of F does XoCXlc...=xยข hold. The weight of F, wF, is the total number of elements of M in the various elements x of F. For given integers f and c, we find min wF, where the minimum is taken over all f-element c-antichains F. Daykin [9, has solved this problem for ordinary sets and Clements [3] has solved it for multisets, but only for c = 1.


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