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arXiv · 2108.02729

Counting scattered palindromes in a finite word

Kalpana Mahalingam·Palak Pandoh
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Abstract

We investigate the scattered palindromic subwords in a finite word. We start by characterizing the words with the least number of scattered palindromic subwords. Then, we give an upper bound for the total number of palindromic subwords in a word of length $n$ in terms of Fibonacci number $F_n$ by proving that at most $F_n$ new scattered palindromic subwords can be created on the concatenation of a letter to a word of length $n-1$. We propose a conjecture on the maximum number of scattered palindromic subwords in a word of length $n$ with $q$ distinct letters. We support the conjecture by showing its validity for words where $q\geq \frac{n}{2}$.

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Kalpana Mahalingam, Palak Pandoh. 2021-08-05. Counting scattered palindromes in a finite word. https://arxiv.org/abs/2108.02729

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