{"title":"具有给定零强迫数最大化\\(A_\\alpha \\) -谱半径的团树","authors":"Long Jin, Jianxi Li, Yuan Hou","doi":"10.1007/s00010-024-01125-6","DOIUrl":null,"url":null,"abstract":"<div><p>The <span>\\(A_\\alpha \\)</span>-spectral radius of a graph <i>G</i> is the largest eigenvalue of <span>\\(A_\\alpha (G):=\\alpha D(G)+(1-\\alpha ) A(G)\\)</span> for any real number <span>\\(\\alpha \\in [0,1]\\)</span>, where <i>A</i>(<i>G</i>) and <i>D</i>(<i>G</i>) are the adjacency matrix and the degree matrix of <i>G</i>, respectively. In this paper, we settle the problem of characterizing graphs which attain the maximum <span>\\(A_\\alpha \\)</span>-spectral radius over <span>\\({\\mathscr {B}}(n, k)\\)</span>, the class of clique trees of order <i>n</i> with a zero forcing number <i>k</i>, where <span>\\(0 \\le \\alpha <1\\)</span>, <span>\\(\\left\\lfloor \\frac{n}{2}\\right\\rfloor +1 \\le k \\le n-1\\)</span> and each block is a clique of size at least 3. Moreover, an estimation on the <span>\\(A_\\alpha \\)</span>-spectral radius of the extremal graph is also included. Our result covers a recent result of Das (2023).</p></div>","PeriodicalId":55611,"journal":{"name":"Aequationes Mathematicae","volume":"99 2","pages":"335 - 350"},"PeriodicalIF":0.9000,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Clique trees with a given zero forcing number maximizing the \\\\(A_\\\\alpha \\\\)-spectral radius\",\"authors\":\"Long Jin, Jianxi Li, Yuan Hou\",\"doi\":\"10.1007/s00010-024-01125-6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The <span>\\\\(A_\\\\alpha \\\\)</span>-spectral radius of a graph <i>G</i> is the largest eigenvalue of <span>\\\\(A_\\\\alpha (G):=\\\\alpha D(G)+(1-\\\\alpha ) A(G)\\\\)</span> for any real number <span>\\\\(\\\\alpha \\\\in [0,1]\\\\)</span>, where <i>A</i>(<i>G</i>) and <i>D</i>(<i>G</i>) are the adjacency matrix and the degree matrix of <i>G</i>, respectively. In this paper, we settle the problem of characterizing graphs which attain the maximum <span>\\\\(A_\\\\alpha \\\\)</span>-spectral radius over <span>\\\\({\\\\mathscr {B}}(n, k)\\\\)</span>, the class of clique trees of order <i>n</i> with a zero forcing number <i>k</i>, where <span>\\\\(0 \\\\le \\\\alpha <1\\\\)</span>, <span>\\\\(\\\\left\\\\lfloor \\\\frac{n}{2}\\\\right\\\\rfloor +1 \\\\le k \\\\le n-1\\\\)</span> and each block is a clique of size at least 3. Moreover, an estimation on the <span>\\\\(A_\\\\alpha \\\\)</span>-spectral radius of the extremal graph is also included. Our result covers a recent result of Das (2023).</p></div>\",\"PeriodicalId\":55611,\"journal\":{\"name\":\"Aequationes Mathematicae\",\"volume\":\"99 2\",\"pages\":\"335 - 350\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2024-10-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Aequationes Mathematicae\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s00010-024-01125-6\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Aequationes Mathematicae","FirstCategoryId":"100","ListUrlMain":"https://link.springer.com/article/10.1007/s00010-024-01125-6","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Clique trees with a given zero forcing number maximizing the \(A_\alpha \)-spectral radius
The \(A_\alpha \)-spectral radius of a graph G is the largest eigenvalue of \(A_\alpha (G):=\alpha D(G)+(1-\alpha ) A(G)\) for any real number \(\alpha \in [0,1]\), where A(G) and D(G) are the adjacency matrix and the degree matrix of G, respectively. In this paper, we settle the problem of characterizing graphs which attain the maximum \(A_\alpha \)-spectral radius over \({\mathscr {B}}(n, k)\), the class of clique trees of order n with a zero forcing number k, where \(0 \le \alpha <1\), \(\left\lfloor \frac{n}{2}\right\rfloor +1 \le k \le n-1\) and each block is a clique of size at least 3. Moreover, an estimation on the \(A_\alpha \)-spectral radius of the extremal graph is also included. Our result covers a recent result of Das (2023).
期刊介绍:
aequationes mathematicae is an international journal of pure and applied mathematics, which emphasizes functional equations, dynamical systems, iteration theory, combinatorics, and geometry. The journal publishes research papers, reports of meetings, and bibliographies. High quality survey articles are an especially welcome feature. In addition, summaries of recent developments and research in the field are published rapidly.