Robert Ferguson, Vincent Vatter
We prove that if the prime graphs in a graph class have bounded lettericity, then the entire class has bounded lettericity if and only if it does not contain arbitrary large matchings, co-matchings, or a family of graphs that we call stacked paths.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
We prove that a large family of graphs which are decomposable with respect to the modular decomposition can be reconstructed from their collection of vertex-deleted subgraphs.
Let $H$ be a 3-uniform hypergraph. A tournament $T$ defined on $V(T)=V(H)$ is a realization of $H$ if the edges of $H$ are exactly the 3-element subsets of $V(T)$ that induce 3-cycles. We characterize the 3-uniform hypergraphs that admit realizations by using a suitable modular decomposition.
We shall characterize the structure of invertible substitutions on three-letter alphabet. We show that any invertible substitution, after some cyclic operation, can be written as a finite product of permutations and Fibonacci's substitution. As a consequence, a matrix (of order 3 and with non-negative integral coefficients) is the matrix of an invertible substitution if and only if it is a finite product of non-negative elementary matrices.
Linear clique-width and modular decomposition
本文研究了线性团宽与模分解的关系，证明了遗产类图具有有界线性团宽的充要条件，并扩展了之前关于凝聚图的研究。
Modular Ideals and Factorizations of Affine Hyperplane Arrangements
本文提出超平面排列交集偏序集的理想分解概念，利用莫比乌斯代数推导特征多项式分解，并推广了Stanley和Terao的理论，同时实现了Orlik-Solomon代数的张量分解。
Decline and Fall of the ICALP 2008 Modular Decomposition algorithm
本文通过提供反例，推翻了ICALP 2008论文中关于线性时间模块分解算法的一个关键引理，证明该算法无效。
The modular decomposition of a symmetric map $δ\colon X\times X \to Υ$ (or, equivalently, a set of symmetric binary relations, a 2-structure, or an edge-colored undirected graph) is a natural construction to capture key features of $δ$ in labeled trees. A map $δ$ is explained by a vertex-labeled rooted tree $(T,t)$ if the label $δ(x,y)$ coincides with the label of the last common ancestor of $x$ and $y$ in $T$, i.e., if $δ(x,y)=t(\mathrm{lca}(x,y))$. Only maps whose modular decomposition does not contain prime nodes, i.e., the symbolic ultrametrics, can be exaplained in this manner. Here we co…
Characterization of Word-Representable Graphs using Modular Decomposition
本文通过模分解刻画字表示图类，利用模块的排列表示数与商图表示数确定图的表示数，并解决了图字典积字表示性的开放问题。
Subgraph densities and scaling limits of random graphs with a prescribed modular decomposition
本文研究了具有预设模分解装饰的大型均匀标记随机图，通过组合论证和符号方法计算生成级数，估计了每个图作为导出子图的拷贝数量，并证明了此类随机图在图核空间中向 Brownian 极限对象收敛。
The modular decomposition of a graph is a canonical representation of its modules. Algorithms for computing the modular decomposition of directed and undirected graphs differ significantly, with the undirected case being simpler, and algorithms for directed graphs often work by reducing the problem to decomposing undirected graphs. In this paper we show that transitive acyclic digraphs have the same strong modules as their undirected versions. This simplifies reduction for transitive digraphs, requiring only the computation of strongly connected components. Furthermore, we are interested in pe…
Let A be a collection of n linear hyperplanes in k^l, where k is an algebraically closed field. The Orlik-Terao algebra of A is the subalgebra R(A) of the rational functions generated by reciprocals of linear forms vanishing on hyperplanes of A. It determines an irreducible subvariety of projective space. We show that a flat X of A is modular if and only if R(A) is a split extension of the Orlik-Terao algebra of the subarrangement A_X. This provides another refinement of Stanley's modular factorization theorem and a new characterization of modularity, similar in spirit to the modular fibration…
Given a permutation w, we show that the number of repeated letters in a reduced decomposition of w is always less than or equal to the number of 321- and 3412-patterns appearing in w. Moreover, we prove bijectively that the two quantities are equal if and only if w avoids the ten patterns 4321, 34512, 45123, 35412, 43512, 45132, 45213, 53412, 45312, and 45231.
Given a graph $G$, a subgraph $H$ is isometric if $d_H(u,v) = d_G(u,v)$ for every pair $u,v\in V(H)$, where $d$ is the distance function. A graph $G$ is distance preserving (dp) if it has an isometric subgraph of every possible order. A graph is sequentially distance preserving (sdp) if its vertices can be ordered such that deleting the first $i$ vertices results in an isometric subgraph, for all $i\ge1$. We introduce a generalisation of the lexicographic product of graphs, which can be used to non-trivially describe graphs. This generalisation is the inverse of the modular decomposition of gr…
The concept of descent algebras over a field of characteristic zero is extended to define descent algebras over a field of prime characteristic. Some basic algebraic structure of the latter, including its radical and irreducible modules, is then determined. The decomposition matrix of the descent algebras of Coxeter group types $A$, $B$, and $D$ are calculated, and used to derive a description of the decomposition matrix of an arbitrary descent algebra. The Cartan matrix of a variety of descent algebras over a finite field is then obtained.
Totally $Δ$-Modular Tree Decompositions of Graphic Matrices for Integer Programming
本文提出了一种基于树分解的参数，用于解决具有两个非零条目每行的矩阵的整数规划问题，扩展了传统图分解参数的应用范围，并给出了相关定理的类比。
A sequence of vertices in a graph $G$ with no isolated vertices is called a total dominating sequence if every vertex in the sequence totally dominates at least one vertex that was not totally dominated by preceding vertices in the sequence, and, at the end all vertices of $G$ are totally dominated (by definition a vertex totally dominates its neighbors). The maximum length of a total dominating sequence is called the Grundy total domination number, $γ_{\rm gr}^t(G)$, of $G$, as introduced in [B. Brešar, M.A. Henning, and D. F. Rall, Total dominating sequences in graphs, Discrete Math. 339 (20…
This paper introduces the notion of involution module, the first generalization of the modular decomposition of 2-structure which has a unique linear-sized decomposition tree. We derive an O(n^2) decomposition algorithm and we take advantage of the involution modular decomposition tree to state several algorithmic results. Cographs are the graphs that are totally decomposable w.r.t modular decomposition. In a similar way, we introduce the class of switch cographs, the class of graphs that are totally decomposable w.r.t involution modular decomposition. This class generalizes the class of cogra…
Recoloring via modular decomposition
通过模分解证明了特定图类的可重着色性，展示了素图的着色复杂性及hereditary图类的重着色性质。
The modular decomposition of a graph $G$ is a natural construction to capture key features of $G$ in terms of a labeled tree $(T,t)$ whose vertices are labeled as "series" ($1$), "parallel" ($0$) or "prime". However, full information of $G$ is provided by its modular decomposition tree $(T,t)$ only, if $G$ does not contain prime modules. In this case, $(T,t)$ explains $G$, i.e., $\{x,y\}\in E(G)$ if and only if the lowest common ancestor $\mathrm{lca}_T(x,y)$ of $x$ and $y$ has label "$1$". This information, however, gets lost whenever $(T,t)$ contains vertices with label "prime". In this cont…
Modular Decomposition focuses on repeatedly identifying a module M (a collection of vertices that shares exactly the same neighbourhood outside of M) and collapsing it into a single vertex. This notion of exactitude of neighbourhood is very strict, especially when dealing with real world graphs. We study new ways to relax this exactitude condition. However, generalizing modular decomposition is far from obvious. Most of the previous proposals lose algebraic properties of modules and thus most of the nice algorithmic consequences. We introduce the notion of an (α, β)-module, a relaxation that a…
Parameterized Complexity of (d,r)-Domination via Modular Decomposition
本文研究可用于遏制虚假信息传播的 (d,r)-Domination 问题，借助标准参数与结构参数分析其参数化复杂性，并为若干变体和参数组合提供固定参数算法及多项式压缩/核化结果。
This paper consists of two prongs. Firstly, we prove that any Specht module labelled by a 2-separated partition is semisimple and we completely determine its decomposition as a direct sum of graded simple modules. Secondly, we apply these results and other modular representation theoretic techniques on the study of Kronecker coefficients and hence verify Saxl's conjecture for a large new class of partitions.
Network Representation and Modular Decomposition of Combinatorial Structures: A Galled-Tree Perspective
本文研究组合结构 strudigrams 的网络表示，提出用 galls 局部替换模分解树中的素顶点构建标记 galled-trees，定义并刻画了 galled-tree 可解释（GATEX）strudigrams，证明其识别与重建可在多项式时间内完成。
A transitive decomposition of a graph is a partition of the edge or arc set giving a set of subgraphs which are preserved and permuted transitively by a group of automorphisms of the graph. In this paper we give some background to the study of transitive decompositions and highlight a connection with partial linear spaces. We then describe a simple method for constructing transitive decompositions using graph quotients, and we show how this may be used in an application to modular origami.
Computing Well-Covered Vector Spaces of Graphs using Modular Decomposition
本文基于反邻域和模分解结合高斯消元法，提出了计算图well-covered向量空间的归约方法，为fork-free graph类开发了多项式时间算法，推广了已有结论。
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。