Title
Colored Multipermutations and a Combinatorial Generalization of Worpitzky's Identity
Abstract
Worpitzky's identity, first presented in 1883, expresses n(p) in terms of the Eulerian numbers and binomial coefficients: n(p) = -Sigma(p-1)(i=0) < p i > (n+1 p). Pita-Ruiz recently defined numbers A(a,b,r)(p, i) implicitly to satisfy a generalized Worpitzky identity (an+b r)(p) = Sigma(rp)(i=0) A(a,b,r)(p, i)(n+rp-i rp), and asked whether there is a combinatorial interpretation of the numbers A(a,b,r)(p, i). We provide such a combinatorial interpretation by defining a notion of descents in colored multipermutations, and then proving that A(a,b),(r)(p, i) is equal to the number of colored multipermutations of {1(r), 2(r), ..., p(r)} with a colors and i weak descents. We use this to give combinatorial proofs of several identities involving A(a,b,r)(p, i), including the aforementioned generalized Worpitzky identity.
Year
Venue
DocType
2020
AUSTRALASIAN JOURNAL OF COMBINATORICS
Journal
Volume
ISSN
Citations 
78
2202-3518
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
John Engbers1216.79
Pantone Jay200.34
Stocker Christopher300.34