Detecting palindromes, patterns, and borders in regular languages

Terry Anderson; John Loftus; Narad Rampersad; Nicolae Santean; Jeffrey Shallit

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arXiv · 0711.3183

Detecting palindromes, patterns, and borders in regular languages

Terry Anderson·John Loftus·Narad Rampersad·Nicolae Santean·Jeffrey Shallit

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Abstract

Given a language L and a nondeterministic finite automaton M, we consider whether we can determine efficiently (in the size of M) if M accepts at least one word in L, or infinitely many words. Given that M accepts at least one word in L, we consider how long a shortest word can be. The languages L that we examine include the palindromes, the non-palindromes, the k-powers, the non-k-powers, the powers, the non-powers (also called primitive words), the words matching a general pattern, the bordered words, and the unbordered words.

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Terry Anderson, John Loftus, Narad Rampersad, Nicolae Santean, Jeffrey Shallit. 2008-06-09. Detecting palindromes, patterns, and borders in regular languages. https://arxiv.org/abs/0711.3183

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