English

Squarefree words with interior disposable factors

Combinatorics 2020-07-08 v1 Formal Languages and Automata Theory

Abstract

We give a partial answer to a problem of Harju by constructing an infinite ternary squarefree word ww with the property that for every k3312k \geq 3312 there is an interior length-kk factor of ww that can be deleted while still preserving squarefreeness. We also examine Thue's famous squarefree word (generated by iterating the map 00120 \to 012, 1021 \to 02, 212 \to 1) and characterize the positions ii for which deleting the symbol appearing at position ii preserves squarefreeness.

Keywords

Cite

@article{arxiv.2007.03557,
  title  = {Squarefree words with interior disposable factors},
  author = {Marko Milosevic and Narad Rampersad},
  journal= {arXiv preprint arXiv:2007.03557},
  year   = {2020}
}

Comments

10 pages

R2 v1 2026-06-23T16:55:24.139Z