Shifts of Finite Type Obtained by Forbidding a Single Pattern

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Chandgotia, Nishant, Marcus, Brian, Richey, Jacob, Wu, Chengyu
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911244772966400
author Chandgotia, Nishant
Marcus, Brian
Richey, Jacob
Wu, Chengyu
author_facet Chandgotia, Nishant
Marcus, Brian
Richey, Jacob
Wu, Chengyu
contents Given a finite word $w$, Guibas and Odlyzko (J. Combin. Theory Ser. A, 30, 1981, 183-208) showed that the autocorrelation polynomial $ϕ_w(t)$ of $w$, which records the set of self-overlaps of $w$, explicitly determines for each $n$, the number $|B_n(w)|$ of words of length $n$ that avoid $w$. We consider this and related problems from the viewpoint of symbolic dynamics, focusing on the setting of $X_{\{w\}}$, the space of all bi-infinite sequences that avoid $w$. We first summarize and elaborate upon (J. Combin. Theory Ser. A, 30, 1981, 183-208) and other work to show that the sequence $|B_n(w)|$ is equivalent to several invariants of $X_{\{w\}}$. We then give a finite-state labeled graphical representation $L_w$ of $X_{\{w\}}$ and show that $w$ can be recovered from the graph isomorphism class of the unlabeled version of $L_w$. Using $L_w$, we apply ideas from probability and Perron-Frobenius theory to obtain results comparing features of $X_{\{w\}}$ for different $w$. Next, we give partial results on the problem of classifying the spaces $X_{\{w\}}$ up to conjugacy. Finally, we extend some of our results to spaces of multi-dimensional arrays that avoid a given finite pattern.
format Preprint
id arxiv_https___arxiv_org_abs_2409_09024
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Shifts of Finite Type Obtained by Forbidding a Single Pattern
Chandgotia, Nishant
Marcus, Brian
Richey, Jacob
Wu, Chengyu
Dynamical Systems
Combinatorics
Probability
2020 Primary 37B10, Secondary 60J10
Given a finite word $w$, Guibas and Odlyzko (J. Combin. Theory Ser. A, 30, 1981, 183-208) showed that the autocorrelation polynomial $ϕ_w(t)$ of $w$, which records the set of self-overlaps of $w$, explicitly determines for each $n$, the number $|B_n(w)|$ of words of length $n$ that avoid $w$. We consider this and related problems from the viewpoint of symbolic dynamics, focusing on the setting of $X_{\{w\}}$, the space of all bi-infinite sequences that avoid $w$. We first summarize and elaborate upon (J. Combin. Theory Ser. A, 30, 1981, 183-208) and other work to show that the sequence $|B_n(w)|$ is equivalent to several invariants of $X_{\{w\}}$. We then give a finite-state labeled graphical representation $L_w$ of $X_{\{w\}}$ and show that $w$ can be recovered from the graph isomorphism class of the unlabeled version of $L_w$. Using $L_w$, we apply ideas from probability and Perron-Frobenius theory to obtain results comparing features of $X_{\{w\}}$ for different $w$. Next, we give partial results on the problem of classifying the spaces $X_{\{w\}}$ up to conjugacy. Finally, we extend some of our results to spaces of multi-dimensional arrays that avoid a given finite pattern.
title Shifts of Finite Type Obtained by Forbidding a Single Pattern
topic Dynamical Systems
Combinatorics
Probability
2020 Primary 37B10, Secondary 60J10
url https://arxiv.org/abs/2409.09024