{"id":223,"date":"2024-08-29T18:40:36","date_gmt":"2024-08-29T22:40:36","guid":{"rendered":"https:\/\/people.clas.ufl.edu\/jesse-kim\/?page_id=223"},"modified":"2026-03-19T09:10:31","modified_gmt":"2026-03-19T13:10:31","slug":"combinatorics-seminar","status":"publish","type":"page","link":"https:\/\/people.clas.ufl.edu\/jesse-kim\/combinatorics-seminar\/","title":{"rendered":"Combinatorics Seminar"},"content":{"rendered":"\r\n
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Combinatorics Seminar<\/h1>\n\n\n\n

The Fall 2025 Combinatorics seminar is organized by Miklos Bona<\/p>\n\n\n\n\n\n

It meets Tuesdays P8 (3:00-3:50) in LIT 225.<\/p>\n\n\n\n\n\n\n\n\n\t\n\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t
Date<\/th>Speaker<\/th>Title<\/th>Abstract<\/th>\n<\/tr>\n<\/thead>\n
9\/2<\/td>Miklos Bona<\/td>Stack-sorting preimages and 0-1-trees<\/td>We define a class of partially labeled trees and use them to find simple proofs for two recent enumeration results of Colin Defant concerning<\/td>\n<\/tr>\n
9\/9<\/td>Jack Chou<\/td>Newton polytopes of fireworks Grothendieck polynomials<\/td>We show that the support of a Grothendieck polynomial $\\mathfrak G_w$ of any fireworks permutation is as large as possible: a monomial appears in $\\mathfrak G_w$ if and only if it divides $\\mathbf x^{\\mathrm{wt}(\\overline{D(w)})}$ and is divisible by some monomial appearing in the Schubert polynomial $\\mathfrak S_w$. Our formula implies that the homogenization of $\\mathfrak G_w$ has M-convex support. We also show that for any fireworks permutation $w$, there exists a layered permutation $\\pi(w)$ so that $\\mathrm{supp}(\\mathfrak G_{\\pi(w)})\\supseteq \\mathrm{supp}(\\mathfrak G_w)$. This is joint work with Linus Setiabrata.<\/td>\n<\/tr>\n
9\/16<\/td><\/td><\/td><\/td>\n<\/tr>\n
9\/23<\/td><\/td><\/td><\/td>\n<\/tr>\n
9\/30<\/td>Michael Waite<\/td>Permutations containing r copies of 321<\/td>We will show that the generating function for permutations containing r copies of a 321 pattern is not a rational function. We will then show how to generalize our approach in order to prove a similar result for longer monotone patterns.<\/td>\n<\/tr>\n
10\/7<\/td><\/td><\/td><\/td>\n<\/tr>\n
10\/14<\/td>Andrew Vince<\/td>A Conjecture on Connected Subgroups of a Graph<\/td><\/td>\n<\/tr>\n
10\/21<\/td><\/td><\/td><\/td>\n<\/tr>\n
10\/28<\/td><\/td><\/td><\/td>\n<\/tr>\n
11\/4<\/td><\/td><\/td><\/td>\n<\/tr>\n
11\/11<\/td><\/td><\/td><\/td>\n<\/tr>\n
11\/18 (Rescheduled to January)<\/td>Nolan Ison<\/td>Zero Forcing on 2-connected Outerplanar Graphs<\/td>Zero Forcing is an `infection' game played on graphs. We start with a subset of vertices, S, that is infected. There is one forcing rule, namely, if u is an infected vertex and exactly one neighbor v of u is not infected, then v becomes infected. We say that u forces v. We call S a Zero Forcing Set in G if every vertex of G eventually becomes infected. A natural question is the following: What is the minimum cardinality of a zero forcing set? In other words, what is the smallest number of originally infected vertices that will end up infecting the entire graph?<\/td>\n<\/tr>\n
12\/2<\/td>Nicholas Van Nimwegen<\/td>Almost distant monotone patterns<\/td>In a previous work, B\u00f3na and Pantone studied permutations that avoided all but one pattern of length k\u00a0that began with a length k-1 increasing subsequence. We draw the connection between that idea and distant patterns, and study similar permutation classes where the index not part of the increasing subsequence can vary. We find a large class of Wilf-Equivalences between k+1\u00a0classes of k\u00a0patterns of length k+1, and outline several classes of unbalanced Wilf-Equivalences related to the first class. Using this, we are also find new bounds on the exponential growth rate on all monotone distant patterns with a single gap constraint.<\/td>\n<\/tr>\n
<\/td><\/td><\/td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\r\n\t\t\t<\/div>\r\n\t\t<\/div>\r\n\t<\/div>\r\n<\/section>\r\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1390,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"featured_post":"","footnotes":"","_links_to":"","_links_to_target":""},"class_list":["post-223","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/pages\/223","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/users\/1390"}],"replies":[{"embeddable":true,"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/comments?post=223"}],"version-history":[{"count":5,"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/pages\/223\/revisions"}],"predecessor-version":[{"id":246,"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/pages\/223\/revisions\/246"}],"wp:attachment":[{"href":"https:\/\/people.clas.ufl.edu\/jesse-kim\/wp-json\/wp\/v2\/media?parent=223"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}