{"title":"若干无限图族的彩虹连通数","authors":"Liam B. Baker, Jonathan Kariv, Ronald J. Maartens","doi":"10.1007/s13370-025-01381-y","DOIUrl":null,"url":null,"abstract":"<div><p>Let <i>G</i> be a nontrivial connected graph with an edge coloring, and let <span>\\(u,v \\in V(G)\\)</span>. A <span>\\(u-v\\)</span> path in <i>G</i> is said to be a <i>rainbow path</i> if no color is repeated on the edges of the path. Similarly, we define a <i>rainbow geodesic</i>. A <i>rainbow connected graph</i> <i>G</i> is a graph with an edge coloring such that every two vertices in <i>G</i> are connected by a rainbow path. Further, a <i>strong rainbow connected graph</i> <i>G</i> is a graph with an edge coloring such that every two vertices in <i>G</i> is connected by a rainbow geodesic. The minimum number of colors needed to make a graph rainbow connected is called the <i>rainbow connection number</i>, denoted <span>\\({{\\,\\textrm{rc}\\,}}(G)\\)</span>, and the minimum number of colors needed to make a graph strong rainbow connected is called the <i>strong rainbow connection number</i>, denoted <span>\\({{\\,\\textrm{src}\\,}}(G)\\)</span>. In this paper we determine <span>\\({{\\,\\textrm{rc}\\,}}(G)\\)</span> and <span>\\({{\\,\\textrm{src}\\,}}(G)\\)</span> when <i>G</i> is a <i>n</i>-dimensional rectangular grid graph, triangular grid graph, hexagonal grid graph, and a (weak) Bruhat graph, respectively. We show for all these families that <span>\\({{\\,\\textrm{src}\\,}}(G)={{\\,\\textrm{diam}\\,}}(G)\\)</span>.</p></div>","PeriodicalId":46107,"journal":{"name":"Afrika Matematika","volume":"36 4","pages":""},"PeriodicalIF":0.7000,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13370-025-01381-y.pdf","citationCount":"0","resultStr":"{\"title\":\"The rainbow connected number of several infinite graph families\",\"authors\":\"Liam B. Baker, Jonathan Kariv, Ronald J. Maartens\",\"doi\":\"10.1007/s13370-025-01381-y\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Let <i>G</i> be a nontrivial connected graph with an edge coloring, and let <span>\\\\(u,v \\\\in V(G)\\\\)</span>. A <span>\\\\(u-v\\\\)</span> path in <i>G</i> is said to be a <i>rainbow path</i> if no color is repeated on the edges of the path. Similarly, we define a <i>rainbow geodesic</i>. A <i>rainbow connected graph</i> <i>G</i> is a graph with an edge coloring such that every two vertices in <i>G</i> are connected by a rainbow path. Further, a <i>strong rainbow connected graph</i> <i>G</i> is a graph with an edge coloring such that every two vertices in <i>G</i> is connected by a rainbow geodesic. The minimum number of colors needed to make a graph rainbow connected is called the <i>rainbow connection number</i>, denoted <span>\\\\({{\\\\,\\\\textrm{rc}\\\\,}}(G)\\\\)</span>, and the minimum number of colors needed to make a graph strong rainbow connected is called the <i>strong rainbow connection number</i>, denoted <span>\\\\({{\\\\,\\\\textrm{src}\\\\,}}(G)\\\\)</span>. In this paper we determine <span>\\\\({{\\\\,\\\\textrm{rc}\\\\,}}(G)\\\\)</span> and <span>\\\\({{\\\\,\\\\textrm{src}\\\\,}}(G)\\\\)</span> when <i>G</i> is a <i>n</i>-dimensional rectangular grid graph, triangular grid graph, hexagonal grid graph, and a (weak) Bruhat graph, respectively. We show for all these families that <span>\\\\({{\\\\,\\\\textrm{src}\\\\,}}(G)={{\\\\,\\\\textrm{diam}\\\\,}}(G)\\\\)</span>.</p></div>\",\"PeriodicalId\":46107,\"journal\":{\"name\":\"Afrika Matematika\",\"volume\":\"36 4\",\"pages\":\"\"},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2025-10-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s13370-025-01381-y.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Afrika Matematika\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s13370-025-01381-y\",\"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/s13370-025-01381-y","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
The rainbow connected number of several infinite graph families
Let G be a nontrivial connected graph with an edge coloring, and let \(u,v \in V(G)\). A \(u-v\) path in G is said to be a rainbow path if no color is repeated on the edges of the path. Similarly, we define a rainbow geodesic. A rainbow connected graphG is a graph with an edge coloring such that every two vertices in G are connected by a rainbow path. Further, a strong rainbow connected graphG is a graph with an edge coloring such that every two vertices in G is connected by a rainbow geodesic. The minimum number of colors needed to make a graph rainbow connected is called the rainbow connection number, denoted \({{\,\textrm{rc}\,}}(G)\), and the minimum number of colors needed to make a graph strong rainbow connected is called the strong rainbow connection number, denoted \({{\,\textrm{src}\,}}(G)\). In this paper we determine \({{\,\textrm{rc}\,}}(G)\) and \({{\,\textrm{src}\,}}(G)\) when G is a n-dimensional rectangular grid graph, triangular grid graph, hexagonal grid graph, and a (weak) Bruhat graph, respectively. We show for all these families that \({{\,\textrm{src}\,}}(G)={{\,\textrm{diam}\,}}(G)\).