English

The Weak Circular Repetition Threshold Over Large Alphabets

Combinatorics 2019-12-25 v1 Discrete Mathematics Formal Languages and Automata Theory

Abstract

The repetition threshold for words on nn letters, denoted \mboxRT(n)\mbox{RT}(n), is the infimum of the set of all rr such that there are arbitrarily long rr-free words over nn letters. A repetition threshold for circular words on nn letters can be defined in three natural ways, which gives rise to the weak, intermediate, and strong circular repetition thresholds for nn letters, denoted \mboxCRT\mboxW(n)\mbox{CRT}_{\mbox{W}}(n), \mboxCRT\mboxI(n)\mbox{CRT}_{\mbox{I}}(n), and \mboxCRT\mboxS(n)\mbox{CRT}_{\mbox{S}}(n), respectively. Currie and the present authors conjectured that \mboxCRT\mboxI(n)=\mboxCRT\mboxW(n)=\mboxRT(n)\mbox{CRT}_{\mbox{I}}(n)=\mbox{CRT}_{\mbox{W}}(n)=\mbox{RT}(n) for all n4n\geq 4. We prove that \mboxCRT\mboxW(n)=\mboxRT(n)\mbox{CRT}_{\mbox{W}}(n)=\mbox{RT}(n) for all n45n\geq 45, which confirms a weak version of this conjecture for all but finitely many values of nn.

Keywords

Cite

@article{arxiv.1912.11388,
  title  = {The Weak Circular Repetition Threshold Over Large Alphabets},
  author = {Lucas Mol and Narad Rampersad},
  journal= {arXiv preprint arXiv:1912.11388},
  year   = {2019}
}

Comments

arXiv admin note: text overlap with arXiv:1911.05779

R2 v1 2026-06-23T12:55:47.443Z