{"title":"On the spectral radius of graphs without a gem","authors":"","doi":"10.1016/j.disc.2024.114171","DOIUrl":null,"url":null,"abstract":"<div><p>The gem is the 5-vertex graph consisting of a 4-vertex path plus a vertex adjacent to each vertex of the path. A graph is said to be gem-free if it does not contain gem as a subgraph. In this paper, we consider the spectral extremal problem for gem-free graphs with given size. The maximum spectral radius of gem-free graphs with size <span><math><mi>m</mi><mo>≥</mo><mn>11</mn></math></span> is obtained, and the unique corresponding extremal graph is determined.</p></div>","PeriodicalId":50572,"journal":{"name":"Discrete Mathematics","volume":null,"pages":null},"PeriodicalIF":0.7000,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Discrete Mathematics","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0012365X24003029","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
The gem is the 5-vertex graph consisting of a 4-vertex path plus a vertex adjacent to each vertex of the path. A graph is said to be gem-free if it does not contain gem as a subgraph. In this paper, we consider the spectral extremal problem for gem-free graphs with given size. The maximum spectral radius of gem-free graphs with size is obtained, and the unique corresponding extremal graph is determined.
期刊介绍:
Discrete Mathematics provides a common forum for significant research in many areas of discrete mathematics and combinatorics. Among the fields covered by Discrete Mathematics are graph and hypergraph theory, enumeration, coding theory, block designs, the combinatorics of partially ordered sets, extremal set theory, matroid theory, algebraic combinatorics, discrete geometry, matrices, and discrete probability theory.
Items in the journal include research articles (Contributions or Notes, depending on length) and survey/expository articles (Perspectives). Efforts are made to process the submission of Notes (short articles) quickly. The Perspectives section features expository articles accessible to a broad audience that cast new light or present unifying points of view on well-known or insufficiently-known topics.