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Related papers: Excluding words from Dyck shifts

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We examine words w satisfying the following property: if x is a subword of w and |x| is at least k for some fixed k, then the reversal of x is not a subword of w.

Combinatorics · Mathematics 2007-05-23 Narad Rampersad , Jeffrey Shallit

We investigate the number of sets of words that can be formed from a finite alphabet, counted by the total length of the words in the set. An explicit expression for the counting sequence is derived from the generating function, and…

Combinatorics · Mathematics 2010-01-26 Stefan Gerhold

We study density of rational languages under shift invariant probability measures on spaces of two-sided infinite words, which generalizes the classical notion of density studied in formal languages and automata theory. The density for a…

Formal Languages and Automata Theory · Computer Science 2025-08-08 Valérie Berthé , Herman Goulet-Ouellet , Dominique Perrin

This article describes the results of a systematic in-depth study of the criteria used for word sense disambiguation. Our study is based on 60 target words: 20 nouns, 20 adjectives and 20 verbs. Our results are not always in line with some…

Computation and Language · Computer Science 2007-05-23 Laurent Audibert

We define outliers as a set of observations which contradicts the proposed mathematical (statistical) model and we discuss the frequently observed types of the outliers. Further we explore what changes in the model have to be made in order…

Probability · Mathematics 2017-01-25 Lev B. Klebanov , Jaromir Antoch , Andrea Karlova , Ashot V. Kakosyan

In this paper, we consider pattern avoidance in a subset of words on $\{1,1,2,2,\dots,n,n\}$ called reverse double lists. In particular a reverse double list is a word formed by concatenating a permutation with its reversal. We enumerate…

Combinatorics · Mathematics 2023-06-22 Monica Anderson , Marika Diepenbroek , Lara Pudwell , Alex Stoll

We study the structure of the language of binary cube-free words. Namely, we are interested in the cube-free words that cannot be infinitely extended preserving cube-freeness. We show the existence of such words with arbitrarily long finite…

Formal Languages and Automata Theory · Computer Science 2011-08-19 Elena A. Petrova , Arseny M. Shur

Extracting frequent words from a collection of texts is commonly performed in many subjects. However, as useful as it is to obtain a collection of commonly occurring words from texts, there is a need for more specific information to be…

Computation and Language · Computer Science 2022-11-01 Ellie Small , Javier Cabrera

The use of terms from natural and social scientific titles and abstracts is studied from the perspective of sublanguages and their specialized dictionaries. Different notions of sublanguage distinctiveness are explored. Objective methods…

cmp-lg · Computer Science 2008-02-03 Robert M. Losee , Stephanie W. Haas

Learning word embeddings using distributional information is a task that has been studied by many researchers, and a lot of studies are reported in the literature. On the contrary, less studies were done for the case of multiple languages.…

Computation and Language · Computer Science 2020-04-15 Marco Berlot , Evan Kaplan

Howie and Duncan observed that a word in a free product with length at least two and which is not a proper power can be decomposed as a product of two cyclic subwords each of which is uniquely positioned. Using this property, they proved…

Group Theory · Mathematics 2018-04-17 Ihechukwu Chinyere

We start by considering binary words containing the minimum possible numbers of squares and antisquares (where an antisquare is a word of the form $x \overline{x}$), and we completely classify which possibilities can occur. We consider…

Formal Languages and Automata Theory · Computer Science 2019-04-22 Tim Ng , Pascal Ochem , Narad Rampersad , Jeffrey Shallit

We construct a binary minimal subshift whose words of length n form a connected subset of the Hamming graph for each n.

Dynamical Systems · Mathematics 2019-01-16 Ville Salo

We propose different ways of lifting the notion of Dyck language from words to 2-dimensional (2D) pictures, by means of new definitions of increasing comprehensiveness. Two of the proposals are based on alternative definitions of a Dyck…

Formal Languages and Automata Theory · Computer Science 2023-09-22 Stefano Crespi Reghizzi , Antonio Restivo , Pierluigi San Pietro

We study substitutive systems generated by nonprimitive substitutions and show that transitive subsystems of substitutive systems are substitutive. As an application we obtain a complete characterisation of the sets of words that can appear…

Combinatorics · Mathematics 2020-09-23 Jakub Byszewski , Jakub Konieczny , Elżbieta Krawczyk

The avoidability, or unavoidability of patterns in words over finite alphabets has been studied extensively. A word (pattern) over a finite set is said to be unavoidable if, for all but finitely many words, there exists a morphism mapping…

Formal Languages and Automata Theory · Computer Science 2019-07-16 Paul Sauer

A permutation is called Grassmannian if it has at most one descent. The study of pattern avoidance in such permutations was initiated by Gil and Tomasko in 2021. We continue this work by studying Grassmannian permutations that avoid an…

Combinatorics · Mathematics 2023-10-13 Krishna Menon , Anurag Singh

In previous work, Currie and Rampersad showed that the growth of the number of binary words avoiding the pattern xxx^R was intermediate between polynomial and exponential. We now show that the same holds for the growth of the number of…

Combinatorics · Mathematics 2015-08-13 James D. Currie , Narad Rampersad

The distribution of frequency counts of distinct words by length in a language's vocabulary will be analyzed using two methods. The first, will look at the empirical distributions of several languages and derive a distribution that…

Computation and Language · Computer Science 2012-07-17 Reginald D. Smith

In this paper, we derive exact formulas for generating functions counting the number of $n$-ary words avoiding strictly increasing subwords of length $k$, and provide some applications of these formulas.

Combinatorics · Mathematics 2025-11-18 Senan Sekhon