Minimal Letter Frequency in n-th Power-Free Binary Words
نویسندگان
چکیده
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 deened through the notion of exponent: a word is x-th power-free for a real x, if it does not contain subwords of exponent x or more. We study the minimal proportion of one letter in an x-th power-free binary word as a function of x and prove, in particular, that this function is discontinuous.
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