论文信息 - A simple counterexample to a conjecture of Rota

A simple counterexample to a conjecture of Rota

Consider the poset Pn of partitions of an n-element set ordered by refinement. Let S(n, k) be the number of partitions containing k blocks. Let Ln be the maximum length of an antichain in Pn Rota conjectured that Ln = maxkS(n, k). In this paper we construct larger antichains for all n sufficiently large.

James B. Shearer | J. Shearer

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