2007/11/21 by Dmitri I. Panyushev, Panyushev, Dmitri I. · 1 citation
Mathematics · #Advanced Differential Equations and Dynamical Systems #Combinatorics (math.CO) #FOS: Mathematics #Representation Theory (math.RT) #math.CO #math.RT
paper · pdf · doi:10.48550/arxiv.0711.3353
12 pages, final version; to appear in Europ. J. Combinatorics
openalex publication_date 2007/11/21 · arxiv created 2008/07/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
For any finite poset P, there is a natural operator X acting on the antichains of P. We discuss conjectural properties of this operator for some graded posets associated with irreducible root systems. In particular, if Δ+ is the set of positive roots and Π is the set of simple roots in Δ+, then we consider the cases P=Δ+ and Δ+∖ Π. For the root system of type An, we consider an X-invariant integer-valued function on the set of antichains of Δ+ and establish some properties of it.