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Related papers: Sequential densities of rational languages

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We relate binary words with a given number of subsequences to continued fractions of rational numbers with a given denominator. We deduce that there are binary strings of length $O(\log n \log \log n)$ with exactly $n$ subsequences; this…

Combinatorics · Mathematics 2022-10-04 Radosław Żak

A causal set is a partially ordered set on a countably infinite ground-set such that each element is above finitely many others. A natural extension of a causal set is an enumeration of its elements which respects the order. We bring…

Probability · Mathematics 2011-09-22 Graham Brightwell , Malwina Luczak

As is the case of many signals produced by complex systems, language presents a statistical structure that is balanced between order and disorder. Here we review and extend recent results from quantitative characterisations of the degree of…

Computation and Language · Computer Science 2015-03-05 Marcelo A Montemurro , Damián H Zanette

The sequence $(x_n)_{n\in\mathbb N} = (2,5,15,51,187,\dots)$ given by the rule $x_n=(2^n+1)(2^{n-1}+1)/3$ appears in several seemingly unrelated areas of mathematics. For example, $x_n$ is the density of a language of words of length $n$…

Combinatorics · Mathematics 2015-08-10 Carlos Segovia , Monika Winklmeier

As a fundamental piece of multi-object Bayesian inference, multi-object density has the ability to describe the uncertainty of the number and values of objects, as well as the statistical correlation between objects, thus perfectly matches…

Systems and Control · Computer Science 2016-03-29 Suqi Li , Wei Yi , Bailu Wang , Lingjiang Kong

In this paper, we introduce a convergence notion for ordered selections. Our convergence notion is based on subpermutation densities and convergences of the marginal distributions. A particular case of this convergence is the well-known…

Probability · Mathematics 2025-11-18 B. Fazekas , I. Fazekas

A causal set is a countably infinite poset in which every element is above finitely many others; causal sets are exactly the posets that have a linear extension with the order-type of the natural numbers -- we call such a linear extension a…

Combinatorics · Mathematics 2012-01-31 Graham Brightwell , Malwina Luczak

We study the notion of limit sets of cellular automata associated with probability measures (mu-limit sets). This notion was introduced by P. Kurka and A. Maass. It is a refinement of the classical notion of omega-limit sets dealing with…

Discrete Mathematics · Computer Science 2007-05-23 Laurent Boyer , Victor Poupet , Guillaume Theyssier

A classical theorem of Szeg\H{o} states that for any probability measure $\mu=w\frac{\mathrm{d}\theta}{2\pi}+\mu_s$ on the unit circle the polynomials are dense in $L^2(\mathbb{T},\mu)$ if and only if $\log(w)\notin L^1(\mathbb{T})$. A…

Classical Analysis and ODEs · Mathematics 2025-11-13 Chiara Paulsen

Making a linguistic theory is like making a programming language: one typically devises a type system to delineate the acceptable utterances and a denotational semantics to explain observations on their behavior. Via this connection, the…

Computation and Language · Computer Science 2007-05-23 Chung-chieh Shan

We consider a type of long-range percolation problem on the positive integers, motivated by earlier work of others on the appearance of (in)finite words within a site percolation model. The main issue is whether a given infinite binary word…

Probability · Mathematics 2008-07-11 Geoffrey R. Grimmett , Thomas M. Liggett , Thomas Richthammer

We give a short proof of the $L^{1}$ criterion for Beurling generalized integers to have a positive asymptotic density. We actually prove the existence of density under a weaker hypothesis. We also discuss related sufficient conditions for…

Number Theory · Mathematics 2019-08-13 Gregory Debruyne , Jasson Vindas

If $G$ is an abelian group, we say $S\subset G$ is a set of recurrence if for every probability measure preserving $G$-system $(X,\mu,T)$ and every $D\subset X$ having $\mu(D)>0$, there is a $g\in S$ such that $\mu(D\cap T^{g}D)>0$. We say…

Dynamical Systems · Mathematics 2024-12-30 John T. Griesmer

In this paper, we study the density of subsets of nonabelian free groups using relative densities of languages. We start by proving some basic properties about the density of a language $L_1$ relative to another language $L_2$ containing…

Group Theory · Mathematics 2026-04-01 André Carvalho

A generalization of numeration system in which the set N of the natural numbers is recognizable by finite automata can be obtained by describing a lexicographically ordered infinite regular language. Here we show that if P belonging to Q[x]…

Computational Complexity · Computer Science 2007-05-23 Michel Rigo

We propose an operational, quantitative definition of intelligence for arbitrary physical systems. The intelligence density of a system is the ratio of the logarithm of its independent outputs to its total description length. A system…

Artificial Intelligence · Computer Science 2026-04-29 Kang-Sin Choi

Given a natural number $k\ge 2$ and a $k$-automatic set $S$ of natural numbers, we show that the lower density and upper density of $S$ are recursively computable rational numbers and we provide an algorithm for computing these quantities.…

Formal Languages and Automata Theory · Computer Science 2021-04-13 Jason P. Bell

We consider the problem of computing the measure of a regular language of infinite binary trees. While the general case remains unsolved, we show that the measure of a language defined by a first-order formula with no descendant relation or…

Logic in Computer Science · Computer Science 2018-09-11 Marcin Przybyłko

Disproving a conjecture of Bleicher and Erd\H{o}s, we show that there exists a lacunary sequence of positive integers such that finite sums of reciprocals of its terms attain all rational numbers from a non-empty open interval. We also…

Number Theory · Mathematics 2025-12-04 Wouter van Doorn , Vjekoslav Kovač

Most research related to unithood were conducted as part of a larger effort for the determination of termhood. Consequently, novelties are rare in this small sub-field of term extraction. In addition, existing work were mostly empirically…

Artificial Intelligence · Computer Science 2008-10-02 Wilson Wong , Wei Liu , Mohammed Bennamoun