{"title":"关于扬诺夫斯基函数广义塞萨罗稳定的一些结果","authors":"M. P. Jeyaraman, T. G. Bhaskar","doi":"10.1007/s13370-024-01182-9","DOIUrl":null,"url":null,"abstract":"<div><p>Let <span>\\(g_1\\)</span> and <span>\\(g_2 \\)</span> be any two analytic functions defined in the unit disc which are normalized by the condition <span>\\(g_1(0)=1=g_2(0)\\)</span> and <span>\\(\\sigma _n^{b-1,c}(z)\\)</span> be the <i>n</i> <i>th</i> Cesàro mean of type <span>\\((b-1,c)\\)</span> for <span>\\(1+b>c>0\\)</span>. Then <span>\\(g_1\\)</span> is generalized Cesàro stable with respect to <span>\\(g_2\\)</span>, whenever </p><div><div><span>$$\\begin{aligned} \\dfrac{\\sigma _n^{b-1,c}(g_1,z)}{g_1(z)}\\prec \\dfrac{1}{g_2(z)}\\quad \\ (z \\in \\Delta ,\\ n \\in \\mathbb {N}_0), \\end{aligned}$$</span></div></div><p>where <span>\\(\\sigma _n^{b-1,c}(g,z) = \\dfrac{1}{B_n} \\sum _{j=0}^{n} B_{n-j} b_j z^j = \\sigma _n^{b-1,c}(z) * g(z)\\)</span>. The main aim of this article is to prove that <span>\\(\\left( {(Az+1)}/{(Bz+1)}\\right) ^\\eta \\)</span> is generalized Cesàro stable with respect to <span>\\((1/(Bz+1)^{\\eta })\\)</span> but not with respect to itself for <span>\\(-1 \\le B < A \\le 0\\)</span> and <span>\\(0<\\eta \\le 1\\)</span>. As an application, we obtain new and existing results on Cesàro stability and stability.</p></div>","PeriodicalId":46107,"journal":{"name":"Afrika Matematika","volume":"35 2","pages":""},"PeriodicalIF":0.9000,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Some results on generalized Cesàro stable of Janowski function\",\"authors\":\"M. P. Jeyaraman, T. G. Bhaskar\",\"doi\":\"10.1007/s13370-024-01182-9\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Let <span>\\\\(g_1\\\\)</span> and <span>\\\\(g_2 \\\\)</span> be any two analytic functions defined in the unit disc which are normalized by the condition <span>\\\\(g_1(0)=1=g_2(0)\\\\)</span> and <span>\\\\(\\\\sigma _n^{b-1,c}(z)\\\\)</span> be the <i>n</i> <i>th</i> Cesàro mean of type <span>\\\\((b-1,c)\\\\)</span> for <span>\\\\(1+b>c>0\\\\)</span>. Then <span>\\\\(g_1\\\\)</span> is generalized Cesàro stable with respect to <span>\\\\(g_2\\\\)</span>, whenever </p><div><div><span>$$\\\\begin{aligned} \\\\dfrac{\\\\sigma _n^{b-1,c}(g_1,z)}{g_1(z)}\\\\prec \\\\dfrac{1}{g_2(z)}\\\\quad \\\\ (z \\\\in \\\\Delta ,\\\\ n \\\\in \\\\mathbb {N}_0), \\\\end{aligned}$$</span></div></div><p>where <span>\\\\(\\\\sigma _n^{b-1,c}(g,z) = \\\\dfrac{1}{B_n} \\\\sum _{j=0}^{n} B_{n-j} b_j z^j = \\\\sigma _n^{b-1,c}(z) * g(z)\\\\)</span>. The main aim of this article is to prove that <span>\\\\(\\\\left( {(Az+1)}/{(Bz+1)}\\\\right) ^\\\\eta \\\\)</span> is generalized Cesàro stable with respect to <span>\\\\((1/(Bz+1)^{\\\\eta })\\\\)</span> but not with respect to itself for <span>\\\\(-1 \\\\le B < A \\\\le 0\\\\)</span> and <span>\\\\(0<\\\\eta \\\\le 1\\\\)</span>. As an application, we obtain new and existing results on Cesàro stability and stability.</p></div>\",\"PeriodicalId\":46107,\"journal\":{\"name\":\"Afrika Matematika\",\"volume\":\"35 2\",\"pages\":\"\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2024-04-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Afrika Matematika\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s13370-024-01182-9\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Afrika Matematika","FirstCategoryId":"1085","ListUrlMain":"https://link.springer.com/article/10.1007/s13370-024-01182-9","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Some results on generalized Cesàro stable of Janowski function
Let \(g_1\) and \(g_2 \) be any two analytic functions defined in the unit disc which are normalized by the condition \(g_1(0)=1=g_2(0)\) and \(\sigma _n^{b-1,c}(z)\) be the nth Cesàro mean of type \((b-1,c)\) for \(1+b>c>0\). Then \(g_1\) is generalized Cesàro stable with respect to \(g_2\), whenever
$$\begin{aligned} \dfrac{\sigma _n^{b-1,c}(g_1,z)}{g_1(z)}\prec \dfrac{1}{g_2(z)}\quad \ (z \in \Delta ,\ n \in \mathbb {N}_0), \end{aligned}$$
where \(\sigma _n^{b-1,c}(g,z) = \dfrac{1}{B_n} \sum _{j=0}^{n} B_{n-j} b_j z^j = \sigma _n^{b-1,c}(z) * g(z)\). The main aim of this article is to prove that \(\left( {(Az+1)}/{(Bz+1)}\right) ^\eta \) is generalized Cesàro stable with respect to \((1/(Bz+1)^{\eta })\) but not with respect to itself for \(-1 \le B < A \le 0\) and \(0<\eta \le 1\). As an application, we obtain new and existing results on Cesàro stability and stability.