{"title":"3-Uniform 超图中的大型 Y3,2 层","authors":"Jie Han , Lin Sun , Guanghui Wang","doi":"10.1016/j.ejc.2024.103976","DOIUrl":null,"url":null,"abstract":"<div><p>Let <span><math><msub><mrow><mi>Y</mi></mrow><mrow><mn>3</mn><mo>,</mo><mn>2</mn></mrow></msub></math></span> be the 3-graph with two edges intersecting in two vertices. We prove that every 3-graph <span><math><mi>H</mi></math></span> on <span><math><mi>n</mi></math></span> vertices with at least <span><math><mrow><mo>max</mo><mfenced><mrow><mfenced><mrow><mfrac><mrow><mn>4</mn><mi>α</mi><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced><mo>,</mo><mfenced><mrow><mfrac><mrow><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced><mo>−</mo><mfenced><mrow><mfrac><mrow><mi>n</mi><mo>−</mo><mi>α</mi><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced></mrow></mfenced><mo>+</mo><mi>o</mi><mrow><mo>(</mo><msup><mrow><mi>n</mi></mrow><mrow><mn>3</mn></mrow></msup><mo>)</mo></mrow></mrow></math></span> edges contains a <span><math><msub><mrow><mi>Y</mi></mrow><mrow><mn>3</mn><mo>,</mo><mn>2</mn></mrow></msub></math></span>-tiling covering more than <span><math><mrow><mn>4</mn><mi>α</mi><mi>n</mi></mrow></math></span> vertices, for sufficiently large <span><math><mi>n</mi></math></span> and <span><math><mrow><mn>0</mn><mo><</mo><mi>α</mi><mo><</mo><mn>1</mn><mo>/</mo><mn>4</mn></mrow></math></span>. The bound on the number of edges is asymptotically best possible and solves a conjecture of the authors for 3-graphs that generalizes the Matching Conjecture of Erdős.</p></div>","PeriodicalId":50490,"journal":{"name":"European Journal of Combinatorics","volume":null,"pages":null},"PeriodicalIF":1.0000,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Large Y3,2-tilings in 3-uniform hypergraphs\",\"authors\":\"Jie Han , Lin Sun , Guanghui Wang\",\"doi\":\"10.1016/j.ejc.2024.103976\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Let <span><math><msub><mrow><mi>Y</mi></mrow><mrow><mn>3</mn><mo>,</mo><mn>2</mn></mrow></msub></math></span> be the 3-graph with two edges intersecting in two vertices. We prove that every 3-graph <span><math><mi>H</mi></math></span> on <span><math><mi>n</mi></math></span> vertices with at least <span><math><mrow><mo>max</mo><mfenced><mrow><mfenced><mrow><mfrac><mrow><mn>4</mn><mi>α</mi><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced><mo>,</mo><mfenced><mrow><mfrac><mrow><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced><mo>−</mo><mfenced><mrow><mfrac><mrow><mi>n</mi><mo>−</mo><mi>α</mi><mi>n</mi></mrow><mrow><mn>3</mn></mrow></mfrac></mrow></mfenced></mrow></mfenced><mo>+</mo><mi>o</mi><mrow><mo>(</mo><msup><mrow><mi>n</mi></mrow><mrow><mn>3</mn></mrow></msup><mo>)</mo></mrow></mrow></math></span> edges contains a <span><math><msub><mrow><mi>Y</mi></mrow><mrow><mn>3</mn><mo>,</mo><mn>2</mn></mrow></msub></math></span>-tiling covering more than <span><math><mrow><mn>4</mn><mi>α</mi><mi>n</mi></mrow></math></span> vertices, for sufficiently large <span><math><mi>n</mi></math></span> and <span><math><mrow><mn>0</mn><mo><</mo><mi>α</mi><mo><</mo><mn>1</mn><mo>/</mo><mn>4</mn></mrow></math></span>. The bound on the number of edges is asymptotically best possible and solves a conjecture of the authors for 3-graphs that generalizes the Matching Conjecture of Erdős.</p></div>\",\"PeriodicalId\":50490,\"journal\":{\"name\":\"European Journal of Combinatorics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2024-04-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"European Journal of Combinatorics\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0195669824000611\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Combinatorics","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0195669824000611","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
Let be the 3-graph with two edges intersecting in two vertices. We prove that every 3-graph on vertices with at least edges contains a -tiling covering more than vertices, for sufficiently large and . The bound on the number of edges is asymptotically best possible and solves a conjecture of the authors for 3-graphs that generalizes the Matching Conjecture of Erdős.
期刊介绍:
The European Journal of Combinatorics is a high standard, international, bimonthly journal of pure mathematics, specializing in theories arising from combinatorial problems. The journal is primarily open to papers dealing with mathematical structures within combinatorics and/or establishing direct links between combinatorics and other branches of mathematics and the theories of computing. The journal includes full-length research papers on important topics.