Square-free Words with Square-free Self-shuffles
نویسندگان
چکیده
We answer a question of Harju: For every n > 3 there is a square-free ternary word of length n with a square-free self-shuffle.
منابع مشابه
Square-free shuffles of words
Let u v denote the set of all shuffles of the words u and v . It is shown that for each integer n ≥ 3 there exists a square-free ternary word u of length n such that u u contains a square-free word. This property is then shown to also hold for infinite words, i.e., there exists an infinite square-free word u on three letters such that u can be shuffled with itself to produce an infinite square-...
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 21 شماره
صفحات -
تاریخ انتشار 2014