论文信息 - On cloud-antichains and related configurations

On cloud-antichains and related configurations

Abstract We introduce the concept of a cloud-antichain, which is a natural generalization of antichains in partially ordered sets, and solve some seemingly basic extrenal problems for them. Following the discovery of our identity (in[1]) we found the ‘missing term’, which converts Bollobas' inequality into an identity. It immediately yields the uniqueness in the Sperner Theorem for unrelated chains of subsets, which are an example of a cloud-antichain.

Rudolf Ahlswede | Z. Zhang

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