{"title":"在一些路径关键的拉姆齐数上","authors":"Ye Wang, Yanyan Song","doi":"10.1007/s10878-025-01312-4","DOIUrl":null,"url":null,"abstract":"<p>For graphs <i>G</i> and <i>H</i>, the Ramsey number <i>R</i>(<i>G</i>, <i>H</i>) is the smallest <i>r</i> such that any red-blue edge coloring of <span>\\(K_r\\)</span> contains a red <i>G</i> or a blue <i>H</i>. The path-critical Ramsey number <span>\\(R_{\\pi }(G,H)\\)</span> is the largest <i>n</i> such that any red-blue edge coloring of <span>\\(K_r \\setminus P_{n}\\)</span> contains a red <i>G</i> or a blue <i>H</i>, where <span>\\(r=R(G,H)\\)</span> and <span>\\(P_{n}\\)</span> is a path of order <i>n</i>. In this note, we show a general upper bound for <span>\\(R_{\\pi }(G,H)\\)</span>, and determine the exact values for some cases of <span>\\(R_{\\pi }(G,H)\\)</span>.</p>","PeriodicalId":50231,"journal":{"name":"Journal of Combinatorial Optimization","volume":"25 1","pages":""},"PeriodicalIF":1.1000,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On some path-critical Ramsey numbers\",\"authors\":\"Ye Wang, Yanyan Song\",\"doi\":\"10.1007/s10878-025-01312-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>For graphs <i>G</i> and <i>H</i>, the Ramsey number <i>R</i>(<i>G</i>, <i>H</i>) is the smallest <i>r</i> such that any red-blue edge coloring of <span>\\\\(K_r\\\\)</span> contains a red <i>G</i> or a blue <i>H</i>. The path-critical Ramsey number <span>\\\\(R_{\\\\pi }(G,H)\\\\)</span> is the largest <i>n</i> such that any red-blue edge coloring of <span>\\\\(K_r \\\\setminus P_{n}\\\\)</span> contains a red <i>G</i> or a blue <i>H</i>, where <span>\\\\(r=R(G,H)\\\\)</span> and <span>\\\\(P_{n}\\\\)</span> is a path of order <i>n</i>. In this note, we show a general upper bound for <span>\\\\(R_{\\\\pi }(G,H)\\\\)</span>, and determine the exact values for some cases of <span>\\\\(R_{\\\\pi }(G,H)\\\\)</span>.</p>\",\"PeriodicalId\":50231,\"journal\":{\"name\":\"Journal of Combinatorial Optimization\",\"volume\":\"25 1\",\"pages\":\"\"},\"PeriodicalIF\":1.1000,\"publicationDate\":\"2025-05-25\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Combinatorial Optimization\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1007/s10878-025-01312-4\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Combinatorial Optimization","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s10878-025-01312-4","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS","Score":null,"Total":0}
For graphs G and H, the Ramsey number R(G, H) is the smallest r such that any red-blue edge coloring of \(K_r\) contains a red G or a blue H. The path-critical Ramsey number \(R_{\pi }(G,H)\) is the largest n such that any red-blue edge coloring of \(K_r \setminus P_{n}\) contains a red G or a blue H, where \(r=R(G,H)\) and \(P_{n}\) is a path of order n. In this note, we show a general upper bound for \(R_{\pi }(G,H)\), and determine the exact values for some cases of \(R_{\pi }(G,H)\).
期刊介绍:
The objective of Journal of Combinatorial Optimization is to advance and promote the theory and applications of combinatorial optimization, which is an area of research at the intersection of applied mathematics, computer science, and operations research and which overlaps with many other areas such as computation complexity, computational biology, VLSI design, communication networks, and management science. It includes complexity analysis and algorithm design for combinatorial optimization problems, numerical experiments and problem discovery with applications in science and engineering.
The Journal of Combinatorial Optimization publishes refereed papers dealing with all theoretical, computational and applied aspects of combinatorial optimization. It also publishes reviews of appropriate books and special issues of journals.