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Related papers: Words with unbounded periodicity complexity

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In this article, we study word equations in free semigroups and the conjecture that the existence of infinitely many solutions entails the existence of solutions with arbitrarily large exponent of periodicity. We examine this question in…

Formal Languages and Automata Theory · Computer Science 2026-02-26 Volker Diekert , Silas Natterer , Alexander Thumm

We consider the number of occurrences of subwords (non-consecutive sub-sequences) in a given word. We first define the notion of subword entropy of a given word that measures the maximal number of occurrences among all possible subwords. We…

Combinatorics · Mathematics 2025-10-06 Wenjie Fang

We introduce and study a complexity function on words $c_x(n),$ called \emph{cyclic complexity}, which counts the number of conjugacy classes of factors of length $n$ of an infinite word $x.$ We extend the well-known Morse-Hedlund theorem…

Formal Languages and Automata Theory · Computer Science 2016-06-29 Julien Cassaigne , Gabriele Fici , Marinella Sciortino , Luca Q. Zamboni

A word is quasiperiodic (or coverable) if it can be covered with occurrences of another finite word, called its quasiperiod. A word is multi-scale quasiperiodic (or multi-scale coverable) if it has infinitely many different quasiperiods.…

Discrete Mathematics · Computer Science 2015-06-30 Guilhem Gamard , Gwenaël Richomme

A palindromic periodicity is a factor of an infinite word $(ps)^\omega$ where $p$ and $s$ are palindromes and the factor has length at least $|ps|$, for example, $accabaccab$. In this paper we describe several ways in which a palindromic…

Combinatorics · Mathematics 2024-05-02 Jamie Simpson

An infinite permutation is a linear order on the set N. We study the properties of infinite permutations generated by fixed points of some uniform binary morphisms, and find the formula for their complexity.

Discrete Mathematics · Computer Science 2011-08-19 Alexander Valyuzhenich

We propose a notion of complexity for oriented conditional term rewrite systems satisfying certain restrictions. This notion is realistic in the sense that it measures not only successful computations, but also partial computations that…

Logic in Computer Science · Computer Science 2019-03-14 Cynthia Kop , Aart Middeldorp , Thomas Sternagel

Nonterminal complexity of a context-free language is the smallest possible number of nonterminals in its generating grammar. While in general case nonterminal complexity computation problem is unsolvable, it can be computed for different…

Formal Languages and Automata Theory · Computer Science 2021-03-23 Dmitry Golubenko

In this paper, we provide a new characterization of uniformly recurrent words with finite defect based on a relation between the palindromic and factor complexity. Furthermore, we introduce a class of morphisms P_ret closed under…

Combinatorics · Mathematics 2013-02-05 Lubomíra Balková , Edita Pelantová , Štěpán Starosta

Following Inoue et al., we define a word to be a repetition if it is a (fractional) power of exponent at least 2. A word has a repetition factorization if it is the product of repetitions. We study repetition factorizations in several…

Formal Languages and Automata Theory · Computer Science 2023-11-30 Jeffrey Shallit , Xinhao Xu

A set X of partial words over a finite alphabet A is called unavoidable if every two-sided infinite word over A has a factor compatible with an element of X. Unlike the case of a set of words without holes, the problem of deciding whether…

Formal Languages and Automata Theory · Computer Science 2017-08-23 Joey Becker , F. Blanchet-Sadri , Laure Flapan , Stephen Watkins

We determine the maximal length of the period of a periodic word defined by $n$ restrictions. It happens to be the corresponding Fibonacci number.

Combinatorics · Mathematics 2013-05-03 Ilya I. Bogdanov , Grigory R. Chelnokov

We show that there exists an uniformly recurrent infinite word whose set of factors is closed under reversal and which has only finitely many palindromic factors.

Discrete Mathematics · Computer Science 2009-03-16 Jean Berstel , Luc Boasson , Olivier Carton , Isabelle Fagnot

Special scattered subwords, in which the gaps are of length from a given set, are defined. The scattered subword complexity, which is the number of such scattered subwords, is computed for rainbow words.

Discrete Mathematics · Computer Science 2011-04-25 Zoltán Kása

The number of frequencies of factors of length $n+1$ in a recurrent aperiodic infinite word does not exceed $3\Delta \C(n)$, where $\Delta \C (n)$ is the first difference of factor complexity, as shown by Boshernitzan. Pelantov\'a together…

Combinatorics · Mathematics 2013-02-05 Lubomira Balkova

The palindromic length of the finite word $v$ is equal to the minimal number of palindromes whose concatenation is equal to $v$. It was conjectured in 2013 that for every infinite aperiodic word $x$, the palindromic length of its factors is…

Combinatorics · Mathematics 2025-09-16 Josef Rukavicka

Rich words are characterized by containing the maximum possible number of distinct palindromes. Several characteristic properties of rich words have been studied; yet the analysis of repetitions in rich words still involves some interesting…

Combinatorics · Mathematics 2019-11-15 Aseem Raj Baranwal , Jeffrey Shallit

We study the asymptotics and fine-scale behavior of quantitative combinatorial measures of infinite words and related dynamical and algebraic structures. We construct infinite recurrent words $w$ whose complexity functions $p_w(n)$ are…

Combinatorics · Mathematics 2025-08-26 Be'eri Greenfeld , Carlos Gustavo Moreira , Efim Zelmanov

We say that an infinite word w is weak abelian periodic if it can be factorized into finite words with the same frequencies of letters. In the paper we study properties of weak abelian periodicity, its relations with balance and frequency.…

Combinatorics · Mathematics 2013-02-19 Sergey Avgustinovich , Svetlana Puzynina

Suppose $G$ is a simple group. For any nontrivial elements $g$ and $h$, $g$ can be written as a finite product of conjugates of $h$ or the inverse of $h$. G is called uniformly simple if the length of such an expression is uniformly…

Group Theory · Mathematics 2011-07-27 Hiroki Kodama