-powers and the Thue-Morse morphism
نویسنده
چکیده
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 ‘overlapfree’ is replaced with ‘ 3 -power-free’. Furthermore, the number 7 3 is best possible.
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