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Related papers: Approximating reals by sums of two rationals

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A reasonably complete theory of the approximation of an irrational by rational fractions whose numerators and denominators lie in prescribed arithmetic progressions is developed in this paper. Results are both, on the one hand, from a…

Number Theory · Mathematics 2014-08-27 Faustin Adiceam

In the present paper we give very simple general statements which deal with approximation of a real number by rationals and are related to isolation phenomenon. In particular we study functions $ f(x)>f_1(x)>0$ such that existence of…

Number Theory · Mathematics 2025-10-16 Sergei Pitcyn , Nikolay Moshchevitin

In this paper we present a new approach to prove effective results in Diophantine approximation. We then use it to prove an effective theorem on the simultaneous approximation of two algebraic numbers satisfying an algebraic equation with…

Number Theory · Mathematics 2020-05-15 Matthias Nickel

We prove a strong simultaneous Diophantine approximation theorem for values of additive and multiplicative functions provided that the functions have certain regularity on the primes.

Number Theory · Mathematics 2009-06-18 Emre Alkan , Kevin Ford , Alexandru Zaharescu

Our goal is to finally settle the persistent problem in Diophantine Approximation of finding best linear approximates. Classical results from the theory of continued fractions provide the solution for the special homogeneous case in the…

Number Theory · Mathematics 2023-01-19 Avraham Bourla

For a given irrational number, we consider the properties of best rational approximations of given parities. There are three different kinds of rational numbers according to the parity of the numerator and denominator, say odd/odd, even/odd…

Number Theory · Mathematics 2024-03-20 Dong Han Kim , Seul Bee Lee , Lingmin Liao

Recently, the authors showed that for every irrational number $\alpha$, there exist infinitely many positive integers $n$ represented by any given positive definite binary quadratic form $Q$, satisfying $||\alpha n||<n^{-(1/2-\varepsilon)}$…

Number Theory · Mathematics 2026-02-04 Stephan Baier , Habibur Rahaman

Dirichlet's uniform approximation theorem is a fundamental result in Diophantine approximation that gives an optimal rate of approximation with a given bound. We study uniform Diophantine approximation properties on the Hecke group $\mathbf…

Number Theory · Mathematics 2025-03-25 Ayreena Bakhtawar , Dong Han Kim , Seul Bee Lee

In 1974, M. B. Nathanson proved that every irrational number $\alpha$ represented by a simple continued fraction with infinitely many elements greater than or equal to $k$ is approximable by an infinite number of rational numbers $p/q$…

Number Theory · Mathematics 2024-07-17 Jaroslav Hančl , Tho Phuoc Nguyen

In this paper, we establish hybrid results on Diophantine approximation with primes from short intervals. In particular, we prove the following result in a slightly modified form: If $\alpha$ is an irrational number having a continued…

Number Theory · Mathematics 2026-04-07 Stephan Baier , Sayantan Roy

In this work we proof the following theorem which is, in addition to someother lemmas, our main result:\noindent \textbf{theorem}. Let$\ X=\{ ( x\_{1}\text{, }%t\_{1}) \text{, }( x\_{2}\text{, }t\_{2}) \text{, ..., }(x\_{n}\text{,…

Number Theory · Mathematics 2016-05-10 Abdelmadjid Boudaoud

We investigate approximation to a given real number by algebraic numbers and algebraic integers of prescribed degree. We deal with both best and uniform approximation, and highlight the similarities and differences compared with the…

Number Theory · Mathematics 2018-12-31 Johannes Schleischitz

Inspired by a problem proposed by Mahler, we will address the following related question, 'How well can irrationals in a missing digit set be approximated by rationals with polynomial denominators?' and prove some related results. To…

Number Theory · Mathematics 2025-12-11 James Wyatt

We prove a refined version of Markov's theorem in Diophantine approximation. More precisely, we characterize completely the set of irrationals $x$ such that $\left|x-\frac{p}{q}\right|<\frac{1}{3q^2}$ has only finitely many rational…

Number Theory · Mathematics 2026-02-11 Zhe Cao , Harold Erazo , Carlos Gustavo Moreira

This paper deals with two main topics related to Diophantine approximation. Firstly, we show that if a point on an algebraic variety is approximable by rational vectors to a sufficiently large degree, the approximating vectors must lie in…

Number Theory · Mathematics 2017-03-21 Johannes Schleischitz

Let $F_{n}$ be the $n$-th Fibonacci number. Put $\varphi=\frac{1+\sqrt5}{2}$. We prove that the following inequalities hold for any real $\alpha$: 1) $\inf_{n \in \mathbb N} ||F_n\alpha||\le\frac{\varphi-1}{\varphi+2}$, 2) $\liminf_{n\to…

Number Theory · Mathematics 2011-12-30 Victoria Zhuravleva

We show the existence of ``good'' approximations to a real number $\gamma$ using rationals with denominators formed by digits $0$ and $1$ in base $b$. We derive an elementary estimate and enhance this result by managing exponential sums.

Number Theory · Mathematics 2025-03-04 Siddharth Iyer

We prove a result related to Dirichlet spectrum for simultaneous approximation to two real numbers in Euclidean norm and badly or very well approximability.

Number Theory · Mathematics 2021-11-25 Renat K. Akhunzhanov , Nikolay G. Moshchevitin

In this paper we develop the convergence theory of simultaneous, inhomogeneous Diophantine approximation on manifolds. A consequence of our main result is that if the manifold $M \subset \mathbb{R}^n$ is of dimension strictly greater than…

Number Theory · Mathematics 2015-12-17 Victor Beresnevich , Robert C. Vaughan , Sanju Velani , Evgeniy Zorin

Let $\alpha$ be an irrational real number. We show that the set of $\epsilon$-badly approximable numbers \[ \mathrm{Bad}^\varepsilon (\alpha) := \{x\in [0,1]\, : \, \liminf_{|q| \to \infty} |q| \cdot \| q\alpha -x \| \geq \varepsilon \} \]…

Number Theory · Mathematics 2018-05-29 Yann Bugeaud , Dong Han Kim , Seonhee Lim , Michał Rams