# Absent Subsequences in Words

@article{Kosche2021AbsentSI, title={Absent Subsequences in Words}, author={Maria Kosche and Tore Ko{\ss} and Florin Manea and Stefan Siemer}, journal={ArXiv}, year={2021}, volume={abs/2108.13968} }

An absent factor of a string w is a string u which does not occur as a contiguous substring (a.k.a. factor) insidew. We extend this well-studied notion and define absent subsequences: a string u is an absent subsequence of a string w if u does not occur as subsequence (a.k.a. scattered factor) inside w. Of particular interest to us are minimal absent subsequences, i.e., absent subsequences whose every subsequence is not absent, and shortest absent subsequences, i.e., absent subsequences of…

## 5 Citations

### Subsequences in Bounded Ranges: Matching and Analysis Problems

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. In this paper, we consider a variant of the classical algorithmic problem of checking whether a given word v is a subsequence of another word w . More precisely, we consider the problem of…

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This work proposes algorithms for finding the longest common Lyndon subsequence of two strings of length n in O(n) time with O( n) space, or online in O (nσ) space and time.

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An algorithm computing the longest periodic subsequence of a string of length n in O(n7) time with O( n4) words of space is presented and improvements are obtained when restricting the exponents or extending the search.

### m-Nearly k-Universal Words - Investigating Simon Congruence

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Determining the index of the Simon congruence is a long outstanding open problem. Two words u and v are called Simon congruent if they have the same set of scattered factors, which are parts of the…

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In this paper we provide an overview of a series of recent results regarding algorithms for searching for subsequences in words or for the analysis of the sets of subsequences occurring in a word.

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