Article ID Journal Published Year Pages File Type
4656223 Journal of Combinatorial Theory, Series A 2009 15 Pages PDF
Abstract

We define a type B derangement polynomial by q-counting derangements by the number of excedances in the hyperoctahedral group Bn. Properties of the derangement polynomial, including the recurrence relation, generating function, real-rootedness, reciprocity and a unimodal decomposition arising from a symmetric function identity, are studied. The results presented generalize and unify earlier ones due to Brenti, Stanley, Stembridge and Zhang.

Related Topics
Physical Sciences and Engineering Mathematics Discrete Mathematics and Combinatorics