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We present explicit descriptions of the decompositions of vertices of a hypercube graph with respect to its distinguished symmetric cycle.

Combinatorics · Mathematics 2021-06-08 Andrey O. Matveev

We present a mathematical framework for describing the topology of configuration spaces for particles on one-connected graphs. In particular, we compute the homology groups over integers for different classes of one-connected graphs. Our…

Mathematical Physics · Physics 2017-05-24 Tomasz Maciążek , Adam Sawicki

For a tree decomposition $\mathcal{T}$ of a graph $G$, let $\mu(\mathcal{T})$ denote the maximum size of an induced matching in $G$ with the property that some bag of $\mathcal{T}$ contains at least one endpoint of every edge of the…

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…

Discrete Mathematics · Computer Science 2013-10-04 Vincent Cohen-Addad , Michel Habib , Fabien de Montgolfier

We show that an algebra over a cyclic operad supplied with an additional linear algebra datum called Hodge decomposition admits a minimal model whose structure maps are given in terms of summation over trees. This minimal model is unique up…

Quantum Algebra · Mathematics 2023-09-07 Joseph Chuang , Andrey Lazarev

We provide a finite equational presentation of graphs of treewidth at most three, solving an instanceof an open problem by Courcelle and Engelfriet. We use a syntax generalising series-parallel expressions, denoting graphs with a small…

Logic in Computer Science · Computer Science 2025-01-23 Amina Doumane , Samuel Humeau , Damien Pous

In this work we study a linear operator $f$ on a pre-euclidean space $\mathcal{V}$ by using properties of a corresponding graph. Given a basis $\B$ of $\mathcal{V}$, we present a decomposition of $\mathcal{V}$ as an orthogonal direct sum of…

Representation Theory · Mathematics 2024-01-24 Hani Abdelwahab , Elisabete Barreiro , Antonio J. Calderón , José M. Sánchez

Let $G$ be a group. \textit{The permutability graph of cyclic subgroups of $G$}, denoted by $\Gamma_c(G)$, is a graph with all the proper cyclic subgroups of $G$ as its vertices and two distinct vertices in $\Gamma_c(G)$ are adjacent if and…

Group Theory · Mathematics 2015-04-06 R. Rajkumar , P. Devi

We show that all the tangles in a finite graph or matroid can be distinguished by a single tree-decomposition that is invariant under the automorphisms of the graph or matroid. This comes as a corollary of a similar decomposition theorem…

Combinatorics · Mathematics 2017-04-19 Reinhard Diestel , Fabian Hundertmark , Sahar Lemanczyk

We introduce a new operation on a class of graphs with the property that the Laplacian eigenvalues of the input and output graphs are related. Based on this operation, we obtain a family of order (square root of n) noncospectral unicyclic…

Combinatorics · Mathematics 2013-04-05 Eliseu Fritscher , Carlos Hoppen , Vilmar Trevisan

We generalize the enhanced power graph by replacing elements with conjugacy classes. The main result of this paper is to determine when this graph is triangle-free.

Group Theory · Mathematics 2025-03-11 Mark L. Lewis , Abbas Mohammadian

We define a statistical ensemble of non-degenerate graphs, i.e. graphs without multiple- and self-connections between nodes. The node degree distribution is arbitrary, but the nodes are assumed to be uncorrelated. This completes our earlier…

Statistical Mechanics · Physics 2009-11-07 Z. Burda , A. Krzywicki

We investigate a descent on simple graphs, starting with the complete graph on $n$ vertices and ending up with the cycle graph by removing one edge after another. We obtain quantitative results showing that graphs with large diameter must…

Combinatorics · Mathematics 2018-02-28 Katja Mönius , Jörn Steuding , Pascal Stumpf

We study the structure of generalized Baumslag-Solitar groups from the point of view of their (usually non-unique) splittings as fundamental groups of graphs of infinite cyclic groups. We find and characterize certain decompositions of…

Group Theory · Mathematics 2016-09-13 Max Forester

The article starts with some introductory material about resolution graphs of normal surface singularities (definitions, topological/homological properties, etc). We then discuss the case when the normal surface singularity is an N-fold…

Algebraic Geometry · Mathematics 2009-09-25 András Némethi

Motivated by a question of Galby, Munaro, and Yang (SoCG 2023) asking whether every graph class of bounded layered tree-independence number admits clique-based separators of sublinear weight, we investigate relations between layered…

Combinatorics · Mathematics 2025-06-17 Clément Dallard , Martin Milanič , Andrea Munaro , Shizhou Yang

A hole in a graph $G$ is an induced cycle of length at least four, and an even hole is a hole of even length. The diamond is the graph obtained from the complete graph $K_4$ by removing an edge. A pyramid is a graph consisting of a triangle…

Combinatorics · Mathematics 2023-09-06 Tara Abrishami , Maria Chudnovsky , Sepehr Hajebi , Sophie Spirkl

We prove that a complete bipartite graph can be decomposed into cycles of arbitrary specified lengths provided that the obvious necessary conditions are satisfied, the length of each cycle is at most the size of the smallest part, and the…

Combinatorics · Mathematics 2012-04-17 Daniel Horsley

We introduce a class of cycles, called nondegenerate, strictly decomposable cycles, and show that the image of each cycle in this class under the refined cycle map to an extension group in the derived category of arithmetic mixed Hodge…

Algebraic Geometry · Mathematics 2007-05-23 Andreas Rosenschon , Morihiko Saito

An independent set in a graph is a set of pairwise non-adjacent vertices. The independence number $\alpha{(G)}$ is the size of a maximum independent set in the graph $G$. The independence polynomial of a graph is the generating function for…

Discrete Mathematics · Computer Science 2022-03-08 Ron Yosef , Matan Mizrachi , Ohr Kadrawi