Binary words avoiding xx^Rx and strongly unimodal sequences
نویسندگان
چکیده
In previous work, Currie and Rampersad showed that the growth of the number of binary words avoiding the pattern xxx R was intermediate between polynomial and exponential. We now show that the same holds for the growth of the number of binary words avoiding the pattern xx R x. Curiously, the analysis for xx R x is much simpler than that for xxx R. We derive our results by giving a bijection between the set of binary words avoiding xx R x and a class of sequences closely related to the class of " strongly unimodal sequences. "
منابع مشابه
Binary Words Avoiding xxx and Strongly Unimodal Sequences
In previous work, Currie and Rampersad showed that the growth of the number of binary words avoiding the pattern xxxR was intermediate between polynomial and exponential. We now show that the same result holds for the growth of the number of binary words avoiding the pattern xxRx. Curiously, the analysis for xxRx is much simpler than that for xxxR. We derive our results by giving a bijection be...
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ورودعنوان ژورنال:
- CoRR
دوره abs/1508.02964 شماره
صفحات -
تاریخ انتشار 2015