{"title":"大型随机树中双子树可能的最大尺寸","authors":"Miklós Bóna, Ovidiu Costin, Boris Pittel","doi":"10.1007/s00026-024-00711-4","DOIUrl":null,"url":null,"abstract":"<p>We call a pair of vertex-disjoint, induced subtrees of a rooted tree twins if they have the same counts of vertices by out-degrees. The likely maximum size of twins in a uniformly random, rooted Cayley tree of size <span>\\(n\\rightarrow \\infty \\)</span> is studied. It is shown that the expected number of twins of size <span>\\((2+\\delta )\\sqrt{\\log n\\cdot \\log \\log n}\\)</span> approaches zero, while the expected number of twins of size <span>\\((2-\\delta )\\sqrt{\\log n\\cdot \\log \\log n}\\)</span> approaches infinity.</p>","PeriodicalId":50769,"journal":{"name":"Annals of Combinatorics","volume":null,"pages":null},"PeriodicalIF":0.6000,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The Likely Maximum Size of Twin Subtrees in a Large Random Tree\",\"authors\":\"Miklós Bóna, Ovidiu Costin, Boris Pittel\",\"doi\":\"10.1007/s00026-024-00711-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>We call a pair of vertex-disjoint, induced subtrees of a rooted tree twins if they have the same counts of vertices by out-degrees. The likely maximum size of twins in a uniformly random, rooted Cayley tree of size <span>\\\\(n\\\\rightarrow \\\\infty \\\\)</span> is studied. It is shown that the expected number of twins of size <span>\\\\((2+\\\\delta )\\\\sqrt{\\\\log n\\\\cdot \\\\log \\\\log n}\\\\)</span> approaches zero, while the expected number of twins of size <span>\\\\((2-\\\\delta )\\\\sqrt{\\\\log n\\\\cdot \\\\log \\\\log n}\\\\)</span> approaches infinity.</p>\",\"PeriodicalId\":50769,\"journal\":{\"name\":\"Annals of Combinatorics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.6000,\"publicationDate\":\"2024-07-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Annals of Combinatorics\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1007/s00026-024-00711-4\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"MATHEMATICS, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Combinatorics","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00026-024-00711-4","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
The Likely Maximum Size of Twin Subtrees in a Large Random Tree
We call a pair of vertex-disjoint, induced subtrees of a rooted tree twins if they have the same counts of vertices by out-degrees. The likely maximum size of twins in a uniformly random, rooted Cayley tree of size \(n\rightarrow \infty \) is studied. It is shown that the expected number of twins of size \((2+\delta )\sqrt{\log n\cdot \log \log n}\) approaches zero, while the expected number of twins of size \((2-\delta )\sqrt{\log n\cdot \log \log n}\) approaches infinity.
期刊介绍:
Annals of Combinatorics publishes outstanding contributions to combinatorics with a particular focus on algebraic and analytic combinatorics, as well as the areas of graph and matroid theory. Special regard will be given to new developments and topics of current interest to the community represented by our editorial board.
The scope of Annals of Combinatorics is covered by the following three tracks:
Algebraic Combinatorics:
Enumerative combinatorics, symmetric functions, Schubert calculus / Combinatorial Hopf algebras, cluster algebras, Lie algebras, root systems, Coxeter groups / Discrete geometry, tropical geometry / Discrete dynamical systems / Posets and lattices
Analytic and Algorithmic Combinatorics:
Asymptotic analysis of counting sequences / Bijective combinatorics / Univariate and multivariable singularity analysis / Combinatorics and differential equations / Resolution of hard combinatorial problems by making essential use of computers / Advanced methods for evaluating counting sequences or combinatorial constants / Complexity and decidability aspects of combinatorial sequences / Combinatorial aspects of the analysis of algorithms
Graphs and Matroids:
Structural graph theory, graph minors, graph sparsity, decompositions and colorings / Planar graphs and topological graph theory, geometric representations of graphs / Directed graphs, posets / Metric graph theory / Spectral and algebraic graph theory / Random graphs, extremal graph theory / Matroids, oriented matroids, matroid minors / Algorithmic approaches