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Related papers: ({\alpha}, {\beta})-Modules in Graphs

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A square (0,1)-matrix X of order n > 0 is called fully indecomposable if there exists no integer k with 0 < k < n, such that X has a k by n-k zero submatrix. A stable set of a graph G is a subset of pairwise nonadjacent vertices. The…

Combinatorics · Mathematics 2007-05-23 Vadim E. Levit , Eugen Mandrescu

We argue that the existing knowledge about modular decomposition of graphs and clan decomposition of 2-structures can be put to use advantageously in a context of data analysis. We show how to obtain visual descriptions of co-occurrence…

Databases · Computer Science 2020-11-03 Marie Ely Piceno , José Luis Balcázar

We generalize the structure theorem of Robertson and Seymour for graphs excluding a fixed graph $H$ as a minor to graphs excluding $H$ as a topological subgraph. We prove that for a fixed $H$, every graph excluding $H$ as a topological…

Data Structures and Algorithms · Computer Science 2015-03-19 Martin Grohe , Dániel Marx

The locality of a graph problem is the smallest distance $T$ such that each node can choose its own part of the solution based on its radius-$T$ neighborhood. In many settings, a graph problem can be solved efficiently with a distributed or…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-12-14 Yi-Jun Chang , Jan Studený , Jukka Suomela

Massive networks have shown that the determination of dense subgraphs, where vertices interact a lot, is necessary in order to visualize groups of common interest, and therefore be able to decompose a big graph into smaller structures. Many…

Social and Information Networks · Computer Science 2016-04-29 Etienne Callies , Tomás Yany-Anich

For a graph consider the pairs of disjoint matchings which union contains as many edges as possible, and define a parameter $\alpha$ which eqauls the cardinality of the largest matching in those pairs. Also, define $\betta$ to be the…

Discrete Mathematics · Computer Science 2009-09-29 R. R. Kamalian , V. V. Mkrtchyan

We describe a recursive algorithm that decomposes an algebraic set into locally closed equidimensional sets, i.e. sets which each have irreducible components of the same dimension. At the core of this algorithm, we combine ideas from the…

Symbolic Computation · Computer Science 2023-06-12 Christian Eder , Pierre Lairez , Rafael Mohr , Mohab Safey El Din

Degeneration of modules is usually defined geometrically, but due to results of Zwara and Riedtmann we can also define it in terms of exact sequences. This definition also works over fields that are not algebraically closed. Let $k$ be a…

Representation Theory · Mathematics 2015-07-03 Nils Nornes

A {\bf map} is a graph that admits an orientation of its edges so that each vertex has out-degree exactly 1. We characterize graphs which admit a decomposition into $k$ edge-disjoint maps after: (1) the addition of {\it any} $\ell$ edges;…

Combinatorics · Mathematics 2011-11-09 Ruth Haas , Audrey Lee , Ileana Streinu , Louis Theran

The aim of this article is to provide space level maps between configuration spaces of graphs that are predicted by algebraic manipulations of cellular chains. More explicitly, we consider edge contraction and half-edge deletion, and…

Algebraic Topology · Mathematics 2022-01-05 Sanjana Agarwal , Maya Banks , Nir Gadish , Dane Miyata

Let $G$ be a graph of order $n$. A path decomposition $\mathcal{P}$ of $G$ is a collection of edge-disjoint paths that covers all the edges of $G$. Let $p(G)$ denote the minimum number of paths needed in a path decomposition of $G$. Gallai…

Combinatorics · Mathematics 2023-10-18 Xiaohong Chen , Baoyindureng Wu

We pursue the study of edge-irregulators of graphs, which were recently introduced in [Fioravantes et al. Parametrised Distance to Local Irregularity. IPEC, 2024]. That is, we are interested in the parameter Ie(G), which, for a given graph…

Combinatorics · Mathematics 2025-11-19 Julien Bensmail , Noémie Catherinot , Foivos Fioravantes , Clara Marcille , Nacim Oijid

We focus on the detection of communities in multi-scale networks, namely networks made of different levels of organization and in which modules exist at different scales. It is first shown that methods based on modularity are not…

Physics and Society · Physics 2010-09-14 Renaud Lambiotte

Let $F_k$ be the set of graphs on $k$ vertices. For a graph $G$, a $k$-decomposition is a set of induced subgraphs of $G$, each isomorphic to an element of $F_k$, such that each pair of vertices of $G$ is in exactly one element of the set.…

Combinatorics · Mathematics 2019-02-05 Raphael Yuster

We state a combinatorial optimization problem whose feasible solutions define both a decomposition and a node labeling of a given graph. This problem offers a common mathematical abstraction of seemingly unrelated computer vision tasks,…

Computer Vision and Pattern Recognition · Computer Science 2017-02-22 Evgeny Levinkov , Jonas Uhrig , Siyu Tang , Mohamed Omran , Eldar Insafutdinov , Alexander Kirillov , Carsten Rother , Thomas Brox , Bernt Schiele , Bjoern Andres

We prove algorithmic weak and \Szemeredi{} regularity lemmas for several classes of sparse graphs in the literature, for which only weak regularity lemmas were previously known. These include core-dense graphs, low threshold rank graphs,…

Data Structures and Algorithms · Computer Science 2025-05-30 Greg Bodwin , Santosh Vempala

For every positive integer $n$, we find a complete classification for planar graphs according to the collection of numbers of common neighbours for every $n$-tuple of distinct vertices. Our results expand the literature on planar graphical…

Combinatorics · Mathematics 2025-11-25 Riccardo W. Maffucci

Motivated by applications in social and biological network analysis, we introduce a new form of agnostic clustering termed~\emph{motif correlation clustering}, which aims to minimize the cost of clustering errors associated with both edges…

Data Structures and Algorithms · Computer Science 2018-11-07 Pan Li , Gregory J. Puleo , Olgica Milenkovic

Let $G$ be a graph of order $n$. A path decomposition $\mathcal{P}$ of $G$ is a collection of edge-disjoint paths that covers all the edges of $G$. Let $p(G)$ denote the minimum number of paths needed in a path decomposition of $G$. Gallai…

Combinatorics · Mathematics 2023-10-19 Xiaohong Chen , Baoyindureng Wu

We introduce the tree-decomposition-based parameter totally $\Delta$-modular treewidth (TDM-treewidth) for matrices with two nonzero entries per row. We show how to solve integer programs whose matrices have bounded TDM-treewidth in…

Combinatorics · Mathematics 2026-04-27 Caleb McFarland