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arXiv 1204.2180math.COcs.DMq-bio.QM
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词的一个正则引理与孪生子

A regularity lemma and twins in words

Maria Axenovich, Yury Person, Svetlana Puzynina

摘要:

对于单词$S$,令$f(S)$为最大整数$m$,使得存在两个长度为$m$的不相交的相同(分散)子字。令$f(n, Σ) = \min \{f(S): S \text{is of length} n, \text{over alphabet} Σ\}$。这里,它表明,\[2f(n, \{0,1\}) = n-o(n)\]使用的正则性引理的话。也就是说,任何长度为$n$的二进制字都可以被分成两个相同的子字(被称为双(twins)),并且可能还有长度为$o(n)$的剩余子字。一个类似的结果被证明为$k$相同的子字的一个词在一个字母表,最多$k$字母。

英文摘要:

For a word $S$, let $f(S)$ be the largest integer $m$ such that there are two disjoints identical (scattered) subwords of length $m$. Let $f(n, Σ) = \min \{f(S): S \text{is of length} n, \text{over alphabet} Σ\}$. Here, it is shown that \[2f(n, \{0,1\}) = n-o(n)\] using the regularity lemma for words. I.e., any binary word of length $n$ can be split into two identical subwords (referred to as twins) and, perhaps, a remaining subword of length $o(n)$. A similar result is proven for $k$ identical subwords of a word over an alphabet with at most $k$ letters.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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