Repetition Threshold for Circular Words
نویسنده
چکیده
We find the threshold between avoidable and unavoidable repetitions in circular words over k letters for any k > 6. Namely, we show that the number CRT(k) = ⌈k/2⌉+1 ⌈k/2⌉ satisfies the following properties. For any n there exists a k-ary circular word of length n containing no repetition of exponent greater than CRT(k). On the other hand, k-ary circular words of some lengths must have a repetition of exponent at least CRT(k).
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 19 شماره
صفحات -
تاریخ انتشار 2012