3 papers
math.CO2025
Cylindric growth diagrams, walks in simplices, and exclusion processes
Sergi Elizalde
We establish bijections between three classes of combinatorial objects that have been studied in very different contexts: lattice walks in simplicial regions as introduced by Morti…
math.CO2024
Enumeration of interval-closed sets via Motzkin paths and quarter-plane walks
Sergi Elizalde, Nadia Lafrenière, Joel Brewster Lewis +3
We find a generating function for interval-closed sets of the product of two chains poset by constructing a bijection to certain bicolored Motzkin paths. We also find a functional…
math.CO2024
Counting pattern-avoiding permutations by big descents
Sergi Elizalde, Johnny Rivera, Yan Zhuang
A descent of a permutation is called a big descent if ; denote the number of big descents of by . We study…