{"title":"P5-free图的列表r色着色","authors":"Xuanhe Jia, Fengxia Liu, Baiyun Ji, Zihang Zhao","doi":"10.1016/j.amc.2025.129742","DOIUrl":null,"url":null,"abstract":"<div><div>Given a list <span><math><mi>L</mi></math></span> of graph <span><math><mi>G</mi></math></span>, an <span><math><mrow><mo>(</mo><mi>L</mi><mo>,</mo><mi>r</mi><mo>)</mo></mrow></math></span>-coloring of graph <span><math><mi>G</mi></math></span> is a proper coloring such that the color of vertex <span><math><mi>v</mi></math></span> belongs to its list <span><math><mrow><mi>L</mi><mo>(</mo><mi>v</mi><mo>)</mo></mrow></math></span>, and each vertex of degree <span><math><mrow><msub><mi>d</mi><mi>G</mi></msub><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow></mrow></math></span> is adjcent to vertices with at least <span><math><mrow><mi>min</mi><mrow><mo>{</mo><mi>r</mi><mo>,</mo><msub><mi>d</mi><mi>G</mi></msub><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow><mo>}</mo></mrow></mrow></math></span> different colors. The list <span><math><mi>r</mi></math></span>-hued chromatic number, denoted by <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>, is the smallest integer <span><math><mi>k</mi></math></span> such that for any <span><math><mi>k</mi></math></span>-list <span><math><mi>L</mi></math></span> of <span><math><mi>G</mi></math></span>, <span><math><mi>G</mi></math></span> has an <span><math><mrow><mo>(</mo><mi>L</mi><mo>,</mo><mi>r</mi><mo>)</mo></mrow></math></span>-coloring. We prove the following: <span><math><mrow><mo>(</mo><mi>i</mi><mo>)</mo></mrow></math></span> If <span><math><mrow><mi>G</mi><mo>=</mo><mi>G</mi><mo>(</mo><mi>U</mi><mo>,</mo><mi>V</mi><mo>)</mo></mrow></math></span> is a connected <span><math><msub><mi>P</mi><mn>5</mn></msub></math></span>-free bipartite graph and min <span><math><mrow><mo>{</mo><mo>|</mo><mi>U</mi><mo>|</mo><mo>,</mo><mo>|</mo><mi>V</mi><mo>|</mo><mo>}</mo><mo>=</mo><mi>s</mi></mrow></math></span>, then <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>≤</mo><mi>max</mi><mo>{</mo><mn>2</mn><mi>r</mi><mo>,</mo></mrow></mrow></math></span> <span><math><mrow><mi>s</mi><mo>+</mo><mn>1</mn><mo>}</mo></mrow></math></span>. <span><math><mrow><mo>(</mo><mi>i</mi><mi>i</mi><mo>)</mo></mrow></math></span> If <span><math><mi>G</mi></math></span> is a connected <span><math><msub><mi>P</mi><mn>5</mn></msub></math></span>-free graph and <span><math><mrow><mi>r</mi><mo>≤</mo><mn>3</mn></mrow></math></span>, then <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>≤</mo><mi>r</mi><msub><mi>χ</mi><mi>L</mi></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"511 ","pages":"Article 129742"},"PeriodicalIF":3.4000,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The list r-hued coloring of P5-free graph\",\"authors\":\"Xuanhe Jia, Fengxia Liu, Baiyun Ji, Zihang Zhao\",\"doi\":\"10.1016/j.amc.2025.129742\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Given a list <span><math><mi>L</mi></math></span> of graph <span><math><mi>G</mi></math></span>, an <span><math><mrow><mo>(</mo><mi>L</mi><mo>,</mo><mi>r</mi><mo>)</mo></mrow></math></span>-coloring of graph <span><math><mi>G</mi></math></span> is a proper coloring such that the color of vertex <span><math><mi>v</mi></math></span> belongs to its list <span><math><mrow><mi>L</mi><mo>(</mo><mi>v</mi><mo>)</mo></mrow></math></span>, and each vertex of degree <span><math><mrow><msub><mi>d</mi><mi>G</mi></msub><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow></mrow></math></span> is adjcent to vertices with at least <span><math><mrow><mi>min</mi><mrow><mo>{</mo><mi>r</mi><mo>,</mo><msub><mi>d</mi><mi>G</mi></msub><mrow><mo>(</mo><mi>v</mi><mo>)</mo></mrow><mo>}</mo></mrow></mrow></math></span> different colors. The list <span><math><mi>r</mi></math></span>-hued chromatic number, denoted by <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>, is the smallest integer <span><math><mi>k</mi></math></span> such that for any <span><math><mi>k</mi></math></span>-list <span><math><mi>L</mi></math></span> of <span><math><mi>G</mi></math></span>, <span><math><mi>G</mi></math></span> has an <span><math><mrow><mo>(</mo><mi>L</mi><mo>,</mo><mi>r</mi><mo>)</mo></mrow></math></span>-coloring. We prove the following: <span><math><mrow><mo>(</mo><mi>i</mi><mo>)</mo></mrow></math></span> If <span><math><mrow><mi>G</mi><mo>=</mo><mi>G</mi><mo>(</mo><mi>U</mi><mo>,</mo><mi>V</mi><mo>)</mo></mrow></math></span> is a connected <span><math><msub><mi>P</mi><mn>5</mn></msub></math></span>-free bipartite graph and min <span><math><mrow><mo>{</mo><mo>|</mo><mi>U</mi><mo>|</mo><mo>,</mo><mo>|</mo><mi>V</mi><mo>|</mo><mo>}</mo><mo>=</mo><mi>s</mi></mrow></math></span>, then <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>≤</mo><mi>max</mi><mo>{</mo><mn>2</mn><mi>r</mi><mo>,</mo></mrow></mrow></math></span> <span><math><mrow><mi>s</mi><mo>+</mo><mn>1</mn><mo>}</mo></mrow></math></span>. <span><math><mrow><mo>(</mo><mi>i</mi><mi>i</mi><mo>)</mo></mrow></math></span> If <span><math><mi>G</mi></math></span> is a connected <span><math><msub><mi>P</mi><mn>5</mn></msub></math></span>-free graph and <span><math><mrow><mi>r</mi><mo>≤</mo><mn>3</mn></mrow></math></span>, then <span><math><mrow><msub><mi>χ</mi><mrow><mi>L</mi><mo>,</mo><mi>r</mi></mrow></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>≤</mo><mi>r</mi><msub><mi>χ</mi><mi>L</mi></msub><mrow><mo>(</mo><mi>G</mi><mo>)</mo></mrow></mrow></math></span>.</div></div>\",\"PeriodicalId\":55496,\"journal\":{\"name\":\"Applied Mathematics and Computation\",\"volume\":\"511 \",\"pages\":\"Article 129742\"},\"PeriodicalIF\":3.4000,\"publicationDate\":\"2025-09-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Applied Mathematics and Computation\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0096300325004679\",\"RegionNum\":2,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATHEMATICS, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Mathematics and Computation","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0096300325004679","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
Given a list of graph , an -coloring of graph is a proper coloring such that the color of vertex belongs to its list , and each vertex of degree is adjcent to vertices with at least different colors. The list -hued chromatic number, denoted by , is the smallest integer such that for any -list of , has an -coloring. We prove the following: If is a connected -free bipartite graph and min , then . If is a connected -free graph and , then .
期刊介绍:
Applied Mathematics and Computation addresses work at the interface between applied mathematics, numerical computation, and applications of systems – oriented ideas to the physical, biological, social, and behavioral sciences, and emphasizes papers of a computational nature focusing on new algorithms, their analysis and numerical results.
In addition to presenting research papers, Applied Mathematics and Computation publishes review articles and single–topics issues.