Annals of Combinatorics最新文献

On the Ehrhart Theory of Generalized Symmetric Edge Polytopes 关于广义对称边多边形的Ehrhart理论

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-06-23 DOI: 10.1007/s00026-026-00835-9

Robert Davis, Akihiro Higashitani, Hidefumi Ohsugi

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引用次数: 0

Tree-Robinson Dissimilarities Tree-Robinson相异

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-05-08 DOI: 10.1007/s00026-026-00829-7

Pascal Préa

引用次数: 0

Ehrhart Functions of Weighted Lattice Points 加权格点的Ehrhart函数

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-05-05 DOI: 10.1007/s00026-026-00822-0

Jesús A. De Loera, Carlos E. Valencia, Rafael H. Villarreal, Chengyang Wang

引用次数: 0

Counting Permutations by Alternating Runs via Hetyei–Reiner Trees 通过Hetyei-Reiner树交替运行计数排列

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-04-01 DOI: 10.1007/s00026-026-00817-x

Qiongqiong Pan, Yunze Wang, Jiang Zeng

引用次数: 0

Coalescence Probabilities of Cycle Products 循环产物的聚结概率

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-03-02 DOI: 10.1007/s00026-026-00810-4

Holden Mui

引用次数: 0

A Polynomial Bosonic Form of Statistical Configuration Sums and the Odd/Even Minimal Excludant in Integer Partitions 统计组态和的多项式玻色子形式及整数分区的奇偶极小不相容

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2026-02-06 DOI: 10.1007/s00026-025-00792-9

Taichiro Takagi

引用次数: 0

Hydra Graphs for Graph LP Algebras 图LP代数的Hydra图

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2025-12-19 DOI: 10.1007/s00026-025-00797-4

Esther Banaian, Sunita Chepuri, Elizabeth Kelley, Sylvester W. Zhang

引用次数: 0

The Multiplicity of Eigenvalues of (A_{alpha }) of Trees 树的(A_{alpha })特征值的多重性

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2025-12-17 DOI: 10.1007/s00026-025-00796-5

Zhibin Du

{"title":"The Multiplicity of Eigenvalues of (A_{alpha }) of Trees","authors":"Zhibin Du","doi":"10.1007/s00026-025-00796-5","DOIUrl":"10.1007/s00026-025-00796-5","url":null,"abstract":"<div>Let T be a tree on n vertices. For (alpha in [0,1),) let (A_{alpha }(T) = alpha D(T)+(1 - alpha ) A(T),) where D(T) is the degree diagonal matrix of T and A(T) is the adjacency matrix of T. Denote by (m_{A_{alpha }(T),theta }) the multiplicity of (theta ) as an eigenvalue of (A_{alpha }(T).) When (alpha = frac{1}{2}) (aiming to the Laplacian matrix of T), it is known in Akbari et al. (Linear Algebra Appl 586:262–273, 2020) that (m_{A_{alpha }(T),theta } le frac{n - 3}{2},) and when (alpha = 0) (aiming to the adjacency matrix of T), the upper bound of (m_{A_{alpha }(T),theta }) for any fixed real number (theta ) was recently obtained in Du and Huang (Linear Algebra Appl 654:56–68, 2022). In this paper, we establish an upper bound of (m_{A_{alpha }(T),theta }) for any (alpha in [0,1)) and any fixed real number (theta ,) unifying and generalizing the above-mentioned results about the multiplicities of eigenvalues of the adjacency matrix and Laplacian matrix of trees.</div>","PeriodicalId":50769,"journal":{"name":"Annals of Combinatorics","volume":"30 3","pages":"945 - 964"},"PeriodicalIF":0.8,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recursions for Multi-Component Extensions of the q-Dyson Constant Term Identity q-Dyson常数项恒等式的多分量扩展的递归

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2025-11-28 DOI: 10.1007/s00026-025-00790-x

Wenlong Jiang, Suzhen Wen, Yueming Zhong, Yue Zhou

引用次数: 0

Sign Patterns of Certain Infinite Products 某些无穷积的符号模式

IF 0.8 4区数学

Annals of Combinatorics Pub Date : 2025-11-27 DOI: 10.1007/s00026-025-00795-6

Zeyu Huang, Timothy Huber, James McLaughlin, Pengjun Wang, Yan Xu, Dongxi Ye

引用次数: 0