MATH Seminar

Title: Homogeneous Substructures in Ordered Matchings
Seminar: Combinatorics
Speaker: Andrzej Rucinski of Adam Mickiewicz University, Poznan
Contact: Liana Yepremyan, liana.yepremyan@emory.edu
Date: 2024-03-29 at 4:00PM
Venue: MSC W201
Download Flyer
Abstract:
An ordered matching M_n is a partition of a linearly ordered set of size 2n into n pairs (called edges). Taking the linear ordering into account, every pair of edges forms one of three patterns: AABB, ABBA, or ABAB. A submatching with all pairs of edges forming the same pattern is called a clique. In my talk, I will first show an Erdos-Szekeres type result guaranteeing a large clique in every matching M_n. Then I will move on to a random (uniform) setting and investigate the largest size of a clique of a given type (pattern) present in almost all matchings. Finally, I will attempt to generalize these results to r-uniform hypermatchings, that is, partitions of a linearly ordered set of size rn into n r-element subsets. This is joint work with Andrzej Dudek and Jarek Grytczuk.

See All Seminars