{"title":"The sharp bound of the third Hankel determinant for starlike functions","authors":"B. Kowalczyk, A. Lecko, D. K. Thomas","doi":"10.1515/forum-2021-0308","DOIUrl":null,"url":null,"abstract":"Abstract In this paper, we prove the sharp inequality | H 3 , 1 ( f ) | ≤ 4 / 9 \\lvert H_{3,1}(f)\\rvert\\leq 4/9 for starlike functions 𝑓, where H 3 , 1 ( f ) H_{3,1}(f) is the third Hankel determinant, thus solving a long-standing problem.","PeriodicalId":12433,"journal":{"name":"Forum Mathematicum","volume":"34 1","pages":"1249 - 1254"},"PeriodicalIF":1.0000,"publicationDate":"2022-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"10","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Forum Mathematicum","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1515/forum-2021-0308","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: 10
Abstract
Abstract In this paper, we prove the sharp inequality | H 3 , 1 ( f ) | ≤ 4 / 9 \lvert H_{3,1}(f)\rvert\leq 4/9 for starlike functions 𝑓, where H 3 , 1 ( f ) H_{3,1}(f) is the third Hankel determinant, thus solving a long-standing problem.
期刊介绍:
Forum Mathematicum is a general mathematics journal, which is devoted to the publication of research articles in all fields of pure and applied mathematics, including mathematical physics. Forum Mathematicum belongs to the top 50 journals in pure and applied mathematics, as measured by citation impact.