English

Two-block substitutions and morphic words

Combinatorics 2023-02-21 v2

Abstract

We consider in general two-block substitutions and their fixed points. We prove that some of them have a simple structure: their fixed points are morphic sequences. Others are intrinsically more complex, such as the Kolakoski sequence. We prove this for the Thue-Morse sequence in base 3/2.

Keywords

Cite

@article{arxiv.2202.13548,
  title  = {Two-block substitutions and morphic words},
  author = {Michel Dekking and Mike Keane},
  journal= {arXiv preprint arXiv:2202.13548},
  year   = {2023}
}
R2 v1 2026-06-24T09:55:46.496Z