On Shuffling of Infinite Square-Free Words
نویسندگان
چکیده
In this paper we answer two recent questions from Charlier et al. (2014) and Harju (2013) about self-shuffling words. An infinite word w is called self-shuffling, if w = ∏∞ i=0 UiVi = ∏∞ i=0 Ui = ∏∞ i=0 Vi for some finite words Ui, Vi. Harju recently asked whether square-free self-shuffling words exist. We answer this question affirmatively. Besides that, we build an infinite word such that no word in its shift orbit closure is self-shuffling, answering positively a question of Charlier et al.
منابع مشابه
Infinite square-free self-shuffling words
An infinite word w is called self-shuffling, if w = ∏ ∞ i=0 UiVi = ∏ ∞ i=0 Ui = ∏ ∞ i=0 Vi for some finite words Ui, Vi. Harju [4] recently asked whether square-free self-shuffling words exist. We answer this question affirmatively.
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 22 شماره
صفحات -
تاریخ انتشار 2015