There Are Ternary Circular Square-Free Words of Length n for n≥ 18

2002/10/11 by James D. Currie · 78 citations
Computer Science · Mathematics · #Algorithms and Data Compression #Combinatorics #Computability, Logic, AI Algorithms #Computer science #Geometry #Mathematics #Square (algebra) #Ternary operation #semigroups and automata theory

paper · pdf · doi:10.37236/1671

published in The Electronic Journal of Combinatorics 9(1) (Electronic Journal of Combinatorics)

openalex publication_date 2002/10/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/05/21

Abstract

There are circular square-free words of length n on three symbols for n≥ 18. This proves a conjecture of R. J. Simpson.

Citations

• Symbolic Dynamics II. Sturmian Trajectories

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