English

Pattern Avoidance Over a Hypergraph

Combinatorics 2021-08-02 v2

Abstract

We consider the problem of bounding the number of permutations σSn\sigma\in S_n that avoid a fixed permutation πSk\pi\in S_k in specific indices given by a kk-uniform hypergraph Λ\Lambda. We obtain relatively sharp bounds in the case where Λ\Lambda is a random hypergraph, and find bounds in the case where Λ\Lambda contains many large cliques. Along the way, we prove a supersaturation version of F\"uredi-Hajnal, which may be of independent interest.

Keywords

Cite

@article{arxiv.1906.09659,
  title  = {Pattern Avoidance Over a Hypergraph},
  author = {Maxwell Fishelson and Benjamin Gunby},
  journal= {arXiv preprint arXiv:1906.09659},
  year   = {2021}
}

Comments

33 pages. v2, some restructuring and edits made for clarity. Added a discussion about concentration results

R2 v1 2026-06-23T10:01:13.775Z