On a conjecture about enumerating (2+2)-free posets

2010/06/07 by Sherry H.F. Yan, Yan, Sherry H. F.
Mathematics · Computer Science · #Advanced Combinatorial Mathematics #Advanced Mathematical Identities #semigroups and automata theory

paper · pdf · doi:10.48550/arxiv.1006.1226

Abstract

Recently, Kitaev and Remmel posed a conjecture concerning the generating function for the number of unlabeled (2+2)-free posets with respect to number of elements and number of minimal elements. In this paper, we present a combinatorial proof of this conjecture.

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