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Related papers: A note on palindromicity

200 papers

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

A two-dimensional ($2$D) word is a $2$D palindrome if it is equal to its reverse and it is an HV-palindrome if all its columns and rows are $1$D palindromes. We study some combinatorial and structural properties of HV-palindromes and its…

Discrete Mathematics · Computer Science 2019-09-18 Kalpana Mahalingam , Palak Pandoh

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

Fixed points ${\bf u}=\varphi({\bf u})$ of marked and primitive morphisms $\varphi$ over arbitrary alphabet are considered. We show that if ${\bf u}$ is palindromic, i.e., its language contains infinitely many palindromes, then some power…

Combinatorics · Mathematics 2015-09-14 Sébastien Labbé , Edita Pelantová

We characterize binary words that have exactly two unbordered conjugates and show that they can be expressed as a product of two palindromes.

Formal Languages and Automata Theory · Computer Science 2019-12-18 Štěpán Holub , Mike Müller

In this paper we prove that for any infinite word W whose set of factors is closed under reversal, the following conditions are equivalent: (I) all complete returns to palindromes are palindromes; (II) P(n) + P(n+1) = C(n+1) - C(n) + 2 for…

Combinatorics · Mathematics 2010-04-08 Michelangelo Bucci , Alessandro De Luca , Amy Glen , Luca Q. Zamboni

We prove a precise formula for the minimal number K(n) such that every binary word of length $n$ can be divided into K(n) palindromes. Also we estimate the average number $\ol K(n)$ of palindromes composing a random binary word of the…

Combinatorics · Mathematics 2011-05-20 Alex Ravsky

A simple Parry number is a real number \beta>1 such that the R\'enyi expansion of 1 is finite, of the form d_\beta(1)=t_1...t_m. We study the palindromic structure of infinite aperiodic words u_\beta that are the fixed point of a…

Combinatorics · Mathematics 2007-05-23 Petr Ambrož , Christiane Frougny , Zuzana Masáková , Edita Pelantová

A palindrome is a word that reads the same left-to-right as right-to-left. We show that every simple group has a finite generating set $X$, such that every element of it can be written as a palindrome in the letters of $X$. Moreover, every…

Group Theory · Mathematics 2014-12-17 Elisabeth Fink , Andreas Thom

We regard a finite word $u=u_1u_2\cdots u_n$ up to word isomorphism as an equivalence relation on $\{1,2,\ldots, n\}$ where $i$ is equivalent to $j$ if and only if $x_i=x_j.$ Some finite words (in particular all binary words) are generated…

Combinatorics · Mathematics 2014-04-04 Tero Harju , Mari Huova , L. Q. Zamboni

The notion of palindromic length of a finite word, as well as an infinite word, was first introduced by Frid, Puzynina and Zamboni\cite{FRID2013737}. They conjectured that if the palindromic length of an infinite word is bounded, then this…

Combinatorics · Mathematics 2019-07-30 Shuo Li

In this paper we consider the palindromes that can be formed by taking unordered sets of $n$ elements from an alphabet of $b$ letters. In particular, we seek to find the probability that given a random member of this space we are able to…

Combinatorics · Mathematics 2016-04-11 Alexander Burlton

We study infinite ternary words that contain few distinct palindromes. In particular, we classify such words according to their critical exponent.

Combinatorics · Mathematics 2026-04-01 Ľubomíra Dvořáková , Lucas Mol , Pascal Ochem

In this book chapter, written in French, we consider the classical family of Sturmian words, defined as the aperiodic infinite words containing only $n+1$ factors of a length $n$, which is the minimal possible value. We will discuss several…

Combinatorics · Mathematics 2019-05-14 Anna Frid

It is known that each word of length $n$ contains at most $n+1$ distinct palindromes. A finite rich word is a word with maximal number of palindromic factors. The definition of palindromic richness can be naturally extended to infinite…

Formal Languages and Automata Theory · Computer Science 2023-06-22 Francesco Dolce , Edita Pelantová

We generalize recent work of Andrews, Just, and Simay on modular palindromic compositions and anti-palindromic compositions by viewing all compositions partially (modular) palindromic or anti-palindromic. More precisely, we enumerate…

Combinatorics · Mathematics 2023-03-20 Jia Huang

We demonstrate that discrete m-functions with eventually periodic continued fraction coefficients have an algebraic relationship to their second solution if and only if the periodic part of the sequence of continued fraction coefficients is…

Number Theory · Mathematics 2022-05-16 Hunter Handley , Brian Simanek

Palindromes are those reduced words of free products of groups that coincide with their reverse words. We prove that a free product of groups $G$ has infinite palindromic width, provided that $G$ is not the free product of two cyclic groups…

Group Theory · Mathematics 2007-05-23 Valery Bardakov , Vladimir Tolstykh

We determine the minimum possible critical exponent for all palindromes over finite alphabets.

Formal Languages and Automata Theory · Computer Science 2016-12-21 Jeffrey Shallit

Recently, a new characterization of Lyndon words that are also perfectly clustering was proposed by Lapointe and Reutenauer (2024). A word over a ternary alphabet {a,b,c} is called perfectly clustering Lyndon if and only if it is the…

Combinatorics · Mathematics 2024-06-25 Mélodie Lapointe , Nathan Plourde-Hébert