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Related papers: Strong Repetitions in Sturmian Strings

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We give a combinatorial definition of the second parameter describing Sturmian words, that we call formal intercept, as an infinite Ostrowski expansion. We recall the well-known properties of Sturmian words, study factors graphs and…

Combinatorics · Mathematics 2018-03-07 Caius Wojcik

The multitime multiple recurrences are common in analysis of algorithms, computational biology, information theory, queueing theory, filters theory, statistical physics etc. The theoretical part about them is little or not known. That is…

Dynamical Systems · Mathematics 2015-06-10 Cristian Ghiu , Raluca Tuliga , Constantin Udriste

Let us consider an infinite word and $k\geq 1$ an integer. By steps of $k$, we substitute a letter ofthis infinite word by the power of an external letter. The new word obtaining by this process is called $k$ to $k$ substitution of a power…

Combinatorics · Mathematics 2024-05-31 Moussa Barro , K. Ernest Bognini , Boucaré Kientéga

Trapezoidal words are finite words having at most n+1 distinct factors of length n, for every n>=0. They encompass finite Sturmian words. We distinguish trapezoidal words into two disjoint subsets: open and closed trapezoidal words. A…

Formal Languages and Automata Theory · Computer Science 2011-08-19 Gabriele Fici

We propose novel algorithms for sequence prediction based on ideas from stringology. These algorithms are time and space efficient and satisfy mistake bounds related to particular stringological complexity measures of the sequence. In this…

Formal Languages and Automata Theory · Computer Science 2026-03-31 Vanessa Kosoy

We show that the first-order theory of Sturmian words over Presburger arithmetic is decidable. Using a general adder recognizing addition in Ostrowski numeration systems by Baranwal, Schaeffer and Shallit, we prove that the first-order…

Logic in Computer Science · Computer Science 2024-08-14 Philipp Hieronymi , Dun Ma , Reed Oei , Luke Schaeffer , Christian Schulz , Jeffrey Shallit

An infinite word has the property $R_m$ if every factor has exactly $m$ return words. Vuillon showed that $R_2$ characterizes Sturmian words. We prove that a word satisfies $R_m$ if its complexity function is $(m-1)n+1$ and if it contains…

Combinatorics · Mathematics 2007-09-27 Lubomira Balkova , Edita Pelantova , Wolfgang Steiner

We investigate questions related to the presence of primitive words and Lyndon words in automatic and linearly recurrent sequences. We show that the Lyndon factorization of a k-automatic sequence is itself k-automatic. We also show that the…

Formal Languages and Automata Theory · Computer Science 2012-11-08 Daniel Goc , Kalle Saari , Jeffrey Shallit

In this paper, we describe string attractors of all factors of episturmian sequences and show that their size is equal to the number of distinct letters contained in the factor.

Combinatorics · Mathematics 2022-11-14 Lubomíra Dvořáková

We introduce a subclass of linear recurrence sequences which we call poly-rational sequences because they are denoted by rational expressions closed under sum and product. We show that this class is robust by giving several…

Formal Languages and Automata Theory · Computer Science 2019-08-13 Corentin Barloy , Nathanaël Fijalkow , Nathan Lhote , Filip Mazowiecki

String attractors are a combinatorial tool coming from the field of data compression. It is a set of positions within a word which intersects an occurrence of every factor. While one-sided infinite words admitting a finite string attractor…

Combinatorics · Mathematics 2024-03-21 Pierre Béaur , France Gheeraert , Benjamin Hellouin de Menibus

This note presents an elementary version of Sims's algorithm for computing strong generators of a given perm group, together with a proof of correctness and some notes about appropriate low-level data structures. Upper and lower bounds on…

Group Theory · Mathematics 2008-02-03 Donald E. Knuth

In some particular cases we give criteria for morphic sequences to be almost periodic (=uniformly recurrent). Namely, we deal with fixed points of non-erasing morphisms and with automatic sequences. In both cases a polynomial-time algorithm…

Discrete Mathematics · Computer Science 2007-05-23 Yuri Pritykin

The domains of data mining and knowledge discovery make use of large amounts of textual data, which need to be handled efficiently. Specific problems, like finding the maximum weight ordered common subset of a set of ordered sets or…

Data Structures and Algorithms · Computer Science 2009-12-07 Mugurel Ionut Andreica , Nicolae Tapus

In this paper, we survey the rich theory of infinite episturmian words which generalize to any finite alphabet, in a rather resembling way, the well-known family of Sturmian words on two letters. After recalling definitions and basic…

Combinatorics · Mathematics 2010-03-16 Amy Glen , Jacques Justin

We revisit parallel-innermost term rewriting as a model of parallel computation on inductive data structures and provide a corresponding notion of runtime complexity parametric in the size of the start term. We propose automatic techniques…

Logic in Computer Science · Computer Science 2022-08-02 Thaïs Baudon , Carsten Fuhs , Laure Gonnord

We show that the coding of rotation by $\alpha$ on $m$ intervals with rationally independent lengths can be recoded over $m$ Sturmian words of angle $\alpha.$ More precisely, for a given $m$ an universal automaton is constructed such that…

Combinatorics · Mathematics 2007-05-23 Jean Berstel , Laurent Vuillon

A closed word (a.k.a. periodic-like word or complete first return) is a word whose longest border does not have internal occurrences, or, equivalently, whose longest repeated prefix is not right special. We investigate the structure of…

Formal Languages and Automata Theory · Computer Science 2014-12-02 Golnaz Badkobeh , Gabriele Fici , Zsuzsanna Lipták

A binary word is Sturmian if the occurrences of each letter are balanced, in the sense that in any two factors of the same length, the difference between the number of occurrences of the same letter is at most 1. In digital geometry,…

Discrete Mathematics · Computer Science 2025-11-11 Alessandro De Luca , Gabriele Fici

String matching is the problem of finding all the substrings of a text which match a given pattern. It is one of the most investigated problems in computer science, mainly due to its very diverse applications in several fields. Recently,…

Data Structures and Algorithms · Computer Science 2017-07-04 Domenico Cantone , Simone Faro , Arianna Pavone