A unique extension of rich words

نویسندگان

چکیده

A word $w$ is called rich if it contains $| w|+1$ palindromic factors, including the empty word. We say that a can be extended in at least two ways there are distinct letters $x,y$ such $wx,wy$ rich. Let $R$ denote set of all words. Given $w\in R$, let $K(w)$ words $u\in K(w)$ then $wu\in R$ and $wu$ ways. $\omega(w)=\min\{| u| \mid u\in K(w)\}$ $\phi(n)=\max\{\omega(w)\mid w\in R\mbox{ }| w|=n\}$, where $n>0$. Vesti (2014) showed $\phi(n)\leq 2n$. In other words, says for each $u$ with u|\leq 2| w|$ prove n$. addition we real constant $c>0$ integer $m>0$ $n>m$ $\phi(n)\geq (\frac{2}{9}-c)n$. The results hold finite alphabet having letters.

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ژورنال

عنوان ژورنال: Theoretical Computer Science

سال: 2021

ISSN: ['1879-2294', '0304-3975']

DOI: https://doi.org/10.1016/j.tcs.2021.10.004