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It is well known that the edge vector space of an oriented graph can be decomposed in terms of cycles and cocycles (alias cuts, or bonds), and that a basis for the cycle and the cocycle spaces can be generated by adding and removing edges…

Mathematical Physics · Physics 2015-01-22 Matteo Polettini

Extending the work of Godsil and others, we investigate the notion of the inverse of a graph (specifically, of bipartite graphs with a unique perfect matching). We provide a concise necessary and sufficient condition for the invertibility…

Combinatorics · Mathematics 2011-08-19 Cam McLeman , Erin McNicholas

We present statistics on the decompositions (with respect to a distinguished symmetric 2t-cycle) of vertices of the hypercube graph, whose negative parts are regarded as disjoint unions of two subsets of the ground set {1,...,t} of the…

Combinatorics · Mathematics 2020-08-25 Andrey O. Matveev

We propose an alternative proof concerning necessary and sufficient conditions to split the problem of searching for d-separators and building the skeleton of a DAG into small problems for every node of a separation tree T. The proof is…

Artificial Intelligence · Computer Science 2018-07-02 Mohammad Ali Javidian , Marco Valtorta

We present a general framework to generate trees every vertex of which has a non-negative weight and a color. The colors are used to impose certain restrictions on the weight and colors of other vertices. We first extend the enumeration…

Discrete Mathematics · Computer Science 2024-01-19 Tınaz Ekim , Mordechai Shalom , Mehmet Aziz Yirik

We prove a decomposition theorem for the class of triangle-free graphs that do not contain a subdivision of the complete graph on four vertices as an induced subgraph. We prove that every graph of girth at least~5 in this class is…

Combinatorics · Mathematics 2020-12-01 Nicolas Trotignon , Kristina Vušković

We describe a way to decompose the chromatic symmetric function as a positive sum of smaller pieces. We show that these pieces are $e$-positive for cycles. Then we prove that attaching a cycle to a graph preserves the $e$-positivity of…

Combinatorics · Mathematics 2024-10-30 Foster Tom , Aarush Vailaya

We prove that a graph $G$ contains no induced $5$-vertex path and no induced complement of a $5$-vertex path if and only if $G$ is obtained from $5$-cycles and split graphs by repeatedly applying the following operations: substitution,…

In this article, following [A.~Daneshgar, M.~Hejrati, M.~Madani, {\it On cylindrical graph construction and its applications}, EJC, 23(1) p1.29, 45, 2016] we study the spectra of symmetric cylindrical constructs, generalizing some…

Combinatorics · Mathematics 2016-10-11 Amir Daneshgar , Ali Taherkhani

The complexity of a graph is the number of its labeled spanning trees. In this work complexity is studied in settings that admit regular graphs. An exact formula is established linking complexity of the complement of a regular graph to…

Combinatorics · Mathematics 2025-08-18 Gregory P Constantine , Gregory Magda

This work addresses the intrinsic relationship between trees and networks (i.e. graphs). A complete (invertible) mapping is presented which allows trees to be mapped into weighted graphs and then backmapped into the original tree without…

Physics and Society · Physics 2008-08-07 Luciano da Fontoura Costa , Francisco Aparecido Rodrigues

Every finite graph $G$ can be decomposed in a canonical way that displays its local connectivity-structure [DJKK26]. These decompositions are defined via a suitable more tree-like covering of $G$, whose tangle-tree structure is projected…

Combinatorics · Mathematics 2026-03-20 Raphael W. Jacobs , Paul Knappe , Jan Kurkofka

For a graph $G$ and $S\subset V(G)$, if $G - S$ is acyclic, then $S$ is said to be a decycling set of $G$. The size of a smallest decycling set of $G$ is called the decycling number of $G$. The purpose of this paper is a comprehensive…

Combinatorics · Mathematics 2007-05-23 S. Bau , L. W. Beineke

We deal with the problem of decomposing a complete geometric graph into plane star-forests. In particular, we disprove a recent conjecture by Pach, Saghafian and Schnider by constructing for each $n$ a complete geometric graph on $n$…

Combinatorics · Mathematics 2024-02-20 Todor Antić , Jelena Glišić , Milan Milivojčević

In this work, we study methodical decomposition of an undirected, unweighted complete graph ($K_n$ of order $n$, size $m$) into minimum number of edge-disjoint trees. We find that $x$, a positive integer, is minimum and…

Discrete Mathematics · Computer Science 2024-05-30 Antika Sinha , Sanjoy Kumar Saha , Partha Basuchowdhuri

This paper proposes a novel representation of decomposable graphs based on semi-latent tree-dependent bipartite graphs. The novel representation has two main benefits. First, it enables a form of sub-clustering within maximal cliques of the…

Methodology · Statistics 2017-12-05 Mohamad Elmasri

A three-path-configuration is a graph consisting of three pairwise internally-disjoint paths the union of every two of which is an induced cycle of length at least four. A graph is 3PC-free if no induced subgraph of it is a…

Combinatorics · Mathematics 2025-11-14 Maria Chudnovsky , Sepehr Hajebi , Daniel Lokshtanov , Sophie Spirkl

The square of a connected graph $G$ is obtained from $G$ by adding an edge between every pair of vertices at distance $2$. In this paper we give some upper or lower bounds for the spectral radius of the square of connected graphs, trees and…

Combinatorics · Mathematics 2014-04-30 Yi-Zheng Fan , Long Wang

For any connected multigraph $G=(V,E)$ and any $M\subseteq E$, if $M$ induces an acyclic subgraph of $G$ and removing all edges in $M$ yields a subgraph of $G$ whose components are complete graphs, a formula for $\tau_G(M)$ is obtained,…

Combinatorics · Mathematics 2019-07-18 Fengming Dong

So far, a very large amount of work in Natural Language Processing (NLP) rely on trees as the core mathematical structure to represent linguistic informations (e.g. in Chomsky's work). However, some linguistic phenomena do not cope properly…

Computation and Language · Computer Science 2013-02-27 Guillaume Bonfante , Bruno Guillaume