MULTIFRACTAL ANALYSIS OF CONVERGENCE EXPONENTS FOR PRODUCTS OF CONSECUTIVE PARTIAL QUOTIENTS IN CONTINUED FRACTIONS

  • Lulu FANG ,
  • Jihua MA ,
  • Kunkun SONG ,
  • Xin YANG
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  • 1. School of Mathematics and Statistics, Nanjing University of Science and Technology, Nanjing 210094, China;
    2. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China;
    3. Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education), School of Mathematics and Statistics, Hunan Normal University, Changsha 410081, China
E-mail: fanglulu1230@gmail.com; jhma@whu.edu.cn; xyang567@163.com

Received date: 2023-04-10

  Revised date: 2023-10-21

  Online published: 2024-08-30

Supported by

The research was supported by the Scientific Research Fund of Hunan Provincial Education Department (21B0070), the Natural Science Foundation of Jiangsu Province (BK20231452), the Fundamental Research Funds for the Central Universities (30922010809) and the National Natural Science Foundation of China (11801591, 11971195, 12071171, 12171107, 12201207, 12371072).

Abstract

For each real number $x \in (0,1)$, let $[a_1(x),a_2(x),\cdots , a_n(x),\cdots ]$ denote its continued fraction expansion. We study the convergence exponent defined by $\tau(x):= \inf\Big\{s \geq 0: \sum\limits_{n=1}^{\infty}\big(a_n(x)a_{n+1}(x)\big)^{-s}<\infty\Big\},$ which reflects the growth rate of the product of two consecutive partial quotients. As a main result, the Hausdorff dimensions of the level sets of $\tau(x)$ are determined.

Cite this article

Lulu FANG , Jihua MA , Kunkun SONG , Xin YANG . MULTIFRACTAL ANALYSIS OF CONVERGENCE EXPONENTS FOR PRODUCTS OF CONSECUTIVE PARTIAL QUOTIENTS IN CONTINUED FRACTIONS[J]. Acta mathematica scientia, Series B, 2024 , 44(4) : 1594 -1608 . DOI: 10.1007/s10473-024-0422-6

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