Abstract
In 1982, Séébold showed that the only overlap-free binary words that are the fixed points of non-identity morphisms are the Thue–Morse word and its complement. We strengthen Séébold’s result by showing that the same result holds if the term ‘overlap-free’ is replaced with ‘\(\frac{7}{3}\)-power-free’. Furthermore, the number \(\frac{7}{3}\) is best possible.
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Rampersad, N. (2004). Words Avoiding \(\frac{7}{3}\)-Powers and the Thue–Morse Morphism. In: Calude, C.S., Calude, E., Dinneen, M.J. (eds) Developments in Language Theory. DLT 2004. Lecture Notes in Computer Science, vol 3340. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-30550-7_30
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DOI: https://doi.org/10.1007/978-3-540-30550-7_30
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