English

Extremal bounds for pattern avoidance in multidimensional 0-1 matrices

Combinatorics 2024-11-01 v2

Abstract

A 0-1 matrix MM contains another 0-1 matrix PP if some submatrix of MM can be turned into PP by changing any number of 11-entries to 00-entries. MM is P\mathcal{P}-saturated where P\mathcal{P} is a family of 0-1 matrices if MM avoids every element of P\mathcal{P} and changing any 00-entry of MM to a 11-entry introduces a copy of some element of P\mathcal{P}. The extremal function ex(n,P)\operatorname{ex}(n,\mathcal{P}) and saturation function sat(n,P)\operatorname{sat}(n,\mathcal{P}) are the maximum and minimum possible weight of an n×nn\times n P\mathcal{P}-saturated 0-1 matrix, respectively, and the semisaturation function ssat(n,P)\operatorname{ssat}(n,P) is the minimum possible weight of an n×nn\times n P\mathcal{P}-semisaturated 0-1 matrix MM, i.e., changing any 00-entry in MM to a 11-entry introduces a new copy of some element of P\mathcal{P}. We give upper bounds on parameters of minimally non-O(nd1)O(n^{d-1}) dd-dimensional 0-1 matrices, generalized from minimally nonlinear 0-1 matrices in two dimensions, and we show the existence of infinitely many minimally non-O(nd1)O(n^{d-1}) dd-dimensional 0-1 matrices with all dimensions of length greater than 11. For any positive integers k,dk,d and integer r[0,d1]r\in[0,d-1], we construct a family of dd-dimensional 0-1 matrices with both extremal function and saturation function exactly knrkn^r for sufficiently large nn. We show that no family of dd-dimensional 0-1 matrices has saturation function strictly between O(1)O(1) and Θ(n)\Theta(n) and we construct a family of dd-dimensional 0-1 matrices with bounded saturation function and extremal function Ω(ndϵ)\Omega(n^{d-\epsilon}) for any ϵ>0\epsilon>0. Up to a constant multiplicative factor, we fully settle the problem of characterizing the semisaturation function of families of dd-dimensional 0-1 matrices, which we prove to always be Θ(nr)\Theta(n^r) for some integer r[0,d1]r\in[0,d-1].

Cite

@article{arxiv.2306.11934,
  title  = {Extremal bounds for pattern avoidance in multidimensional 0-1 matrices},
  author = {Jesse Geneson and Shen-Fu Tsai},
  journal= {arXiv preprint arXiv:2306.11934},
  year   = {2024}
}
R2 v1 2026-06-28T11:10:14.883Z