Erdős's integer dilation approximation problem and GCD graphs

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Koukoulopoulos, Dimitris, Lamzouri, Youness, Lichtman, Jared Duker
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866912231498711040
author Koukoulopoulos, Dimitris
Lamzouri, Youness
Lichtman, Jared Duker
author_facet Koukoulopoulos, Dimitris
Lamzouri, Youness
Lichtman, Jared Duker
contents Let $\mathcal{A}\subset\mathbb{R}_{\geqslant1}$ be a countable set such that $\limsup_{x\to\infty}\frac{1}{\log x}\sum_{α\in\mathcal{A}\cap[1,x]}\frac{1}α>0$. We prove that, for every $\varepsilon>0$, there exist infinitely many pairs $(α, β)\in \mathcal{A}^2$ such that $α\neq β$ and $|nα-β| <\varepsilon$ for some positive integer $n$. This resolves a problem of Erdős from 1948. A critical role in the proof is played by the machinery of GCD graphs, which were introduced by the first author and by James Maynard in their work on the Duffin--Schaeffer conjecture in Diophantine approximation.
format Preprint
id arxiv_https___arxiv_org_abs_2502_09539
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Erdős's integer dilation approximation problem and GCD graphs
Koukoulopoulos, Dimitris
Lamzouri, Youness
Lichtman, Jared Duker
Number Theory
Combinatorics
Dynamical Systems
Let $\mathcal{A}\subset\mathbb{R}_{\geqslant1}$ be a countable set such that $\limsup_{x\to\infty}\frac{1}{\log x}\sum_{α\in\mathcal{A}\cap[1,x]}\frac{1}α>0$. We prove that, for every $\varepsilon>0$, there exist infinitely many pairs $(α, β)\in \mathcal{A}^2$ such that $α\neq β$ and $|nα-β| <\varepsilon$ for some positive integer $n$. This resolves a problem of Erdős from 1948. A critical role in the proof is played by the machinery of GCD graphs, which were introduced by the first author and by James Maynard in their work on the Duffin--Schaeffer conjecture in Diophantine approximation.
title Erdős's integer dilation approximation problem and GCD graphs
topic Number Theory
Combinatorics
Dynamical Systems
url https://arxiv.org/abs/2502.09539