Abstract
We show that the minimal proportion of one letter in an n-th power-free binary word is asymptotically 1/n. We also consider a generalization of n-th power-free words defined through the notion of exponent: a word is χ-th power-free for a real χ, if it does not contain subwords of exponent χ or more. We study the minimal proportion of one letter in an χ-th power-free binary word as a function of χ and prove, in particular, that this function is discontinuous.
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Kolpakov, R., Kucherov, G. (1997). Minimal letter frequency in n-th power-free binary words. In: Prívara, I., Ružička, P. (eds) Mathematical Foundations of Computer Science 1997. MFCS 1997. Lecture Notes in Computer Science, vol 1295. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0029978
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DOI: https://doi.org/10.1007/BFb0029978
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