Sign up or sign in
logo

Undergraduate Paper Session

Icon: calendar Undergraduate Paper Session #3.1 | 2026 Mar 27 from 02:00PM to 02:01PM (Central Time (US & Canada)) | Computing and Math 345

‟A Graph on Bumpless Pipe Dreams” by Prashreet Poudel <ppoudel1@catamount.wcu.edu>, Western Carolina University

Abstract:

Bumpless pipe dreams (BPDs) are combinatorial objects introduced in 2018 to study Schubert polynomials. Using results from the literature, we introduce a graph structure on the set of BPDs for a fixed permutation, where the edges are determined by certain local moves. We implemented these objects in SageMath and used our program to generate all 409,113 graphs for small permutations. We analyzed this data to form a conjecture on which permutations have acyclic graphs, which we proved using induction. In this talk, we give a pattern-avoidance condition that is necessary for a permutation’s BPD graph to be a tree.