{"title":"On the Special Value Distribution of Two Classes of Small Multiplicative Functions","authors":"Haihong Fan, Wenguang Zhai","doi":"10.1007/s10114-025-3125-6","DOIUrl":null,"url":null,"abstract":"<div><p>For any real number <i>x</i>, [<i>x</i>] denotes the integer part of <i>x</i>. <span>\\(\\cal{F}\\)</span><sub>1</sub>, <span>\\(\\cal{F}\\)</span><sub>2</sub> denote two multiplicative function classes which are small in numerical sense. In this paper, we study the summation <span>\\(\\sum\\nolimits_{{n\\leq x}}f([x/n])\\)</span> for <i>f</i> ∈ <span>\\(\\cal{F}\\)</span><sub>1</sub>. As specific cases, we take <i>d</i><sup>(<i>e</i>)</sup>(<i>n</i>), <i>β</i>(<i>n</i>), <i>a</i>(<i>n</i>), <i>μ</i><sub>2</sub>(<i>n</i>) denoting the number of exponential divisors of <i>n</i>, the number of square-full divisors of <i>n</i>, the number of non-isomorphic Abelian groups of order <i>n</i>, and the characteristic function of the square-free integers, respectively. In the case of <i>μ</i><sub>2</sub>(<i>n</i>), we improved the result of Liu, Wu and Yang. The sums shaped like <span>\\(\\sum\\nolimits_{{n\\leq x}}f([x/n]+f([x/n]))\\)</span> for <i>f</i> ∈ <span>\\(\\cal{F}\\)</span><sub>2</sub> are also researched.</p></div>","PeriodicalId":50893,"journal":{"name":"Acta Mathematica Sinica-English Series","volume":"41 5","pages":"1407 - 1417"},"PeriodicalIF":0.9000,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Acta Mathematica Sinica-English Series","FirstCategoryId":"100","ListUrlMain":"https://link.springer.com/article/10.1007/s10114-025-3125-6","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
For any real number x, [x] denotes the integer part of x. \(\cal{F}\)1, \(\cal{F}\)2 denote two multiplicative function classes which are small in numerical sense. In this paper, we study the summation \(\sum\nolimits_{{n\leq x}}f([x/n])\) for f ∈ \(\cal{F}\)1. As specific cases, we take d(e)(n), β(n), a(n), μ2(n) denoting the number of exponential divisors of n, the number of square-full divisors of n, the number of non-isomorphic Abelian groups of order n, and the characteristic function of the square-free integers, respectively. In the case of μ2(n), we improved the result of Liu, Wu and Yang. The sums shaped like \(\sum\nolimits_{{n\leq x}}f([x/n]+f([x/n]))\) for f ∈ \(\cal{F}\)2 are also researched.
期刊介绍:
Acta Mathematica Sinica, established by the Chinese Mathematical Society in 1936, is the first and the best mathematical journal in China. In 1985, Acta Mathematica Sinica is divided into English Series and Chinese Series. The English Series is a monthly journal, publishing significant research papers from all branches of pure and applied mathematics. It provides authoritative reviews of current developments in mathematical research. Contributions are invited from researchers from all over the world.