{"title":"贝塔动力系统中实数的近似阶数","authors":"","doi":"10.1016/j.jmaa.2024.128895","DOIUrl":null,"url":null,"abstract":"<div><div>For any real numbers <span><math><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span> and <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span>, denote by <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo></math></span> the partial sum of the first <em>n</em> terms in the <em>β</em>-expansion of <em>x</em>. It is known that for any <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span> and almost all <span><math><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span>, or for any <span><math><mi>x</mi><mo>∈</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span> and almost all <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span>, the approximation order of <em>x</em> by <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo></math></span> is <span><math><msup><mrow><mi>β</mi></mrow><mrow><mo>−</mo><mi>n</mi></mrow></msup></math></span>. Let <span><math><mi>φ</mi><mo>:</mo><mi>N</mi><mo>→</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span> be a positive function. In this paper, we study the Hausdorff dimensions of the following two sets<span><span><span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>β</mi></mrow></msub><mo>(</mo><mi>φ</mi><mo>)</mo><mo>=</mo><mrow><mo>{</mo><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo><mo>:</mo><munder><mrow><mrow><mi>lim</mi></mrow><mspace></mspace><mrow><mi>sup</mi></mrow></mrow><mrow><mi>n</mi><mo>→</mo><mo>∞</mo></mrow></munder><mspace></mspace><mfrac><mrow><msub><mrow><mi>log</mi></mrow><mrow><mi>β</mi></mrow></msub><mo></mo><mo>(</mo><mi>x</mi><mo>−</mo><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo><mo>)</mo></mrow><mrow><mi>φ</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></mfrac><mo>=</mo><mo>−</mo><mn>1</mn><mo>}</mo></mrow><mo>,</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>x</mi></mrow></msub><mo>(</mo><mi>φ</mi><mo>)</mo><mo>=</mo><mrow><mo>{</mo><mi>β</mi><mo>></mo><mn>1</mn><mo>:</mo><munder><mrow><mrow><mi>lim</mi></mrow><mspace></mspace><mrow><mi>sup</mi></mrow></mrow><mrow><mi>n</mi><mo>→</mo><mo>∞</mo></mrow></munder><mspace></mspace><mfrac><mrow><msub><mrow><mi>log</mi></mrow><mrow><mi>β</mi></mrow></msub><mo></mo><mo>(</mo><mi>x</mi><mo>−</mo><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo><mo>)</mo></mrow><mrow><mi>φ</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></mfrac><mo>=</mo><mo>−</mo><mn>1</mn><mo>}</mo></mrow><mo>,</mo></math></span></span></span> and complement the dimension theoretic results of these sets in <span><span>[3]</span></span>, <span><span>[6]</span></span> and <span><span>[18]</span></span>.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":null,"pages":null},"PeriodicalIF":1.2000,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Approximation orders of real numbers in beta-dynamical systems\",\"authors\":\"\",\"doi\":\"10.1016/j.jmaa.2024.128895\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>For any real numbers <span><math><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span> and <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span>, denote by <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo></math></span> the partial sum of the first <em>n</em> terms in the <em>β</em>-expansion of <em>x</em>. It is known that for any <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span> and almost all <span><math><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span>, or for any <span><math><mi>x</mi><mo>∈</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></math></span> and almost all <span><math><mi>β</mi><mo>></mo><mn>1</mn></math></span>, the approximation order of <em>x</em> by <span><math><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo></math></span> is <span><math><msup><mrow><mi>β</mi></mrow><mrow><mo>−</mo><mi>n</mi></mrow></msup></math></span>. Let <span><math><mi>φ</mi><mo>:</mo><mi>N</mi><mo>→</mo><msup><mrow><mi>R</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span> be a positive function. In this paper, we study the Hausdorff dimensions of the following two sets<span><span><span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>β</mi></mrow></msub><mo>(</mo><mi>φ</mi><mo>)</mo><mo>=</mo><mrow><mo>{</mo><mi>x</mi><mo>∈</mo><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo><mo>:</mo><munder><mrow><mrow><mi>lim</mi></mrow><mspace></mspace><mrow><mi>sup</mi></mrow></mrow><mrow><mi>n</mi><mo>→</mo><mo>∞</mo></mrow></munder><mspace></mspace><mfrac><mrow><msub><mrow><mi>log</mi></mrow><mrow><mi>β</mi></mrow></msub><mo></mo><mo>(</mo><mi>x</mi><mo>−</mo><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo><mo>)</mo></mrow><mrow><mi>φ</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></mfrac><mo>=</mo><mo>−</mo><mn>1</mn><mo>}</mo></mrow><mo>,</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>x</mi></mrow></msub><mo>(</mo><mi>φ</mi><mo>)</mo><mo>=</mo><mrow><mo>{</mo><mi>β</mi><mo>></mo><mn>1</mn><mo>:</mo><munder><mrow><mrow><mi>lim</mi></mrow><mspace></mspace><mrow><mi>sup</mi></mrow></mrow><mrow><mi>n</mi><mo>→</mo><mo>∞</mo></mrow></munder><mspace></mspace><mfrac><mrow><msub><mrow><mi>log</mi></mrow><mrow><mi>β</mi></mrow></msub><mo></mo><mo>(</mo><mi>x</mi><mo>−</mo><msub><mrow><mi>S</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>,</mo><mi>β</mi><mo>)</mo><mo>)</mo></mrow><mrow><mi>φ</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></mfrac><mo>=</mo><mo>−</mo><mn>1</mn><mo>}</mo></mrow><mo>,</mo></math></span></span></span> and complement the dimension theoretic results of these sets in <span><span>[3]</span></span>, <span><span>[6]</span></span> and <span><span>[18]</span></span>.</div></div>\",\"PeriodicalId\":50147,\"journal\":{\"name\":\"Journal of Mathematical Analysis and Applications\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2024-09-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Mathematical Analysis and Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022247X24008175\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Mathematical Analysis and Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022247X24008175","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
对于任意实数 x∈[0,1] 和 β>1,用 Sn(x,β)表示 x 的β展开式中前 n 项的部分和。已知对于任意 β>1,且几乎所有 x∈[0,1] 或对于任意 x∈(0,1],且几乎所有 β>1,Sn(x,β)对 x 的逼近阶数是β-n。设 φ:N→R+ 为正函数。本文研究以下两个集合的 Hausdorff 维数Aβ(φ)={x∈[0,1]:limsupn→∞logβ(x-Sn(x,β))φ(n)=-1},Ax(φ)={β>1:limsupn→∞logβ(x-Sn(x,β))φ(n)=-1},并补充了[3]、[6]和[18]中这些集合的维度理论结果。
Approximation orders of real numbers in beta-dynamical systems
For any real numbers and , denote by the partial sum of the first n terms in the β-expansion of x. It is known that for any and almost all , or for any and almost all , the approximation order of x by is . Let be a positive function. In this paper, we study the Hausdorff dimensions of the following two sets and complement the dimension theoretic results of these sets in [3], [6] and [18].
期刊介绍:
The Journal of Mathematical Analysis and Applications presents papers that treat mathematical analysis and its numerous applications. The journal emphasizes articles devoted to the mathematical treatment of questions arising in physics, chemistry, biology, and engineering, particularly those that stress analytical aspects and novel problems and their solutions.
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