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arXiv · 1707.01010

Ins-Robust Primitive Words

Amit Kumar Srivastava·Kalpesh Kapoor
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Abstract

Let Q be the set of primitive words over a finite alphabet with at least two symbols. We characterize a class of primitive words, Q_I, referred to as ins-robust primitive words, which remain primitive on insertion of any letter from the alphabet and present some properties that characterizes words in the set Q_I. It is shown that the language Q_I is dense. We prove that the language of primitive words that are not ins-robust is not context-free. We also present a linear time algorithm to recognize ins-robust primitive words and give a lower bound on the number of n-length ins-robust primitive words.

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Amit Kumar Srivastava, Kalpesh Kapoor. 2017-08-03. Ins-Robust Primitive Words. https://arxiv.org/abs/1707.01010

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