A lower bound for a constant in Shallit's conjecture
نویسندگان
چکیده
We study the Shallit's conjecture which states that an in nite word ! is ultimately periodic if and only if lim n!1 inf jun(!)j n > 3 p5 2 ; where un(!) is the longest su x of length n pre x of ! which occurs also inside length n 1 pre x of !. We prove that a weaker condition holds, namely that the conjecture is true if the constant 3 p5 2 is replaced by 13 p69 10 . TUCS Research Group Mathematical Structures of Computer Science
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تاریخ انتشار 1997