English
Related papers

Related papers: Polynomial representation for the expected length …

200 papers

A universal representation theorem is derived that shows any graph is the intersection graph of one chordal graph, a number of co-bipartite graphs, and one unit interval graph. Central to the the result is the notion of the clique cover…

Combinatorics · Mathematics 2015-04-21 Farhad Shahrokhi

Let $G$ be a connected graph with vertex set $V(G)$, and denote by $d_G(u,v)$ the distance from $u$ to $v$ in $G$, for any $u,v \in V(G)$. The average distance of an $n$-vertex connected graph $G$, denoted by $\mu(G)$, is defined to be the…

Combinatorics · Mathematics 2026-05-07 Zhibin Du , Xuli Qi

We give polynomial time logarithmic approximation guarantees for the budget minimization, as well as for the profit maximization versions of minimum spanning tree interdiction. In this problem, the goal is to remove some edges of an…

Data Structures and Algorithms · Computer Science 2025-07-28 Rafail Ostrovsky , Yuval Rabani , Yoav Siman Tov

We investigate the analytic spread of binomial edge ideals of finite simple graphs. We provide tight bounds for this invariant in general. For special families of graphs (e.g., closed graphs, pseudo-forests), we compute the exact value for…

A spanning tree of a graph $G$ is a connected acyclic spanning subgraph of $G$. We consider enumeration of spanning trees when $G$ is a $2$-tree, meaning that $G$ is obtained from one edge by iteratively adding a vertex whose neighborhood…

Discrete Mathematics · Computer Science 2016-07-21 P. Renjith , N. Sadagopan , Douglas B. West

A network-theoretic approach for determining the complexity of a graph is proposed. This approach is based on the relationship between the linear algebra (theory of determinants) and the graph theory. In this paper we contribute a new…

Discrete Mathematics · Computer Science 2018-12-04 E. M. Badr , B. Mohamed

We obtain an improved lower bound for the regularity of the binomial edge ideals of trees. We prove an upper bound for the regularity of the binomial edge ideals of certain subclass of block-graphs. As a consequence we obtain sharp upper…

Commutative Algebra · Mathematics 2018-04-30 A. V. Jayanthan , N. Narayanan , B. V. Raghavendra Rao

A tree decomposition of a graph facilitates computations by grouping vertices into bags that are interconnected in an acyclic structure, hence their importance in a plethora of problems such as query evaluation over databases and inference…

Data Structures and Algorithms · Computer Science 2018-10-09 Noam Ravid , Dori Medini , Benny Kimelfeld

Let $G$ be a graph of order $n$ and let $\mathcal{L}(G,\lambda)=\sum_{k=0}^n (-1)^{k}c_{k}(G)\lambda^{n-k}$ be the characteristic polynomial of its Laplacian matrix. Motivated by Ili\'{c} and Ili\'{c}'s conjecture [A. Ili\'{c}, M. Ili\'{c},…

Combinatorics · Mathematics 2013-11-11 Jie Zhang , Xiao-Dong Zhang

Let $G$ be a simple graph on $n$ vertices and $\mathcal{I}_G$ denotes parity binomial edge ideal of $G$ in the polynomial ring $S = \mathbb{K}[x_1,\ldots, x_n, y_1, \ldots, y_n].$ We obtain a lower bound for the regularity of parity…

Commutative Algebra · Mathematics 2021-08-20 Arvind Kumar

The independence polynomial of a graph is the generating polynomial for the number of independent sets of each size, and its roots are called {\em independence roots}. We investigate the stability of such polynomials, that is, conditions…

Combinatorics · Mathematics 2018-02-08 Jason Brown , Ben Cameron

Let $\mathcal{T}$ be the set of spanning trees of $G$ and let $L(T)$ be the number of leaves in a tree $T$. The leaf number $L(G)$ of $G$ is defined as $L(G)=\max\{L(T)|T\in \mathcal{T}\}$. Let $G$ be a connected graph of order $n$ and…

Combinatorics · Mathematics 2022-03-08 Jingru Yan

The quadratic minimum spanning tree problem (QMSTP) is the problem of finding a spanning tree of a graph such that the total interaction cost between pairs of edges in the tree is minimized. We first show that most of the bounding…

Optimization and Control · Mathematics 2024-04-09 Renata Sotirov , Zoe Verchére

It is $\mathsf{NP}$-hard to determine the minimum number of branching vertices needed in a single-source distance-preserving subgraph of an undirected graph. We show that this problem can be solved in polynomial time if the input graph is…

Data Structures and Algorithms · Computer Science 2018-10-30 Kshitij Gajjar , Jaikumar Radhakrishnan

We study the problem of maximizing the number of spanning trees in a connected graph by adding at most $k$ edges from a given candidate edge set. We give both algorithmic and hardness results for this problem: - We give a greedy algorithm…

Data Structures and Algorithms · Computer Science 2018-07-17 Huan Li , Stacy Patterson , Yuhao Yi , Zhongzhi Zhang

Among subgraphs with a fixed number of vertices of the regular square lattice, we prove inequalities that essentially say that those with smaller boundaries have larger numbers of spanning trees and vice-versa. As an application, we relate…

Combinatorics · Mathematics 2022-06-06 Kristopher Tapp

We prove that, for an undirected graph with $n$ vertices and $m$ edges, each labeled with a linear function of a parameter $\lambda$, the number of different minimum spanning trees obtained as the parameter varies can be $\Omega(m\log n)$.

Discrete Mathematics · Computer Science 2021-05-13 David Eppstein

In this paper the robust recoverable spanning tree problem with interval edge costs is considered. The complexity of this problem has remained open to date. It is shown that the problem is polynomially solvable, by using an iterative…

Data Structures and Algorithms · Computer Science 2016-03-08 Mikita Hradovich , Adam Kasperski , Pawel Zielinski

We present a new algorithm, which solves the problem of distributively finding a minimum diameter spanning tree of any (non-negatively) real-weighted graph $G = (V,E,\omega)$. As an intermediate step, we use a new, fast, linear-time…

Distributed, Parallel, and Cluster Computing · Computer Science 2013-12-12 Marc Bui , Franck Butelle , Christian Lavault

There are several good reasons you might want to read about uniform spanning trees, one being that spanning trees are useful combinatorial objects. Not only are they fundamental in algebraic graph theory and combinatorial geometry, but they…

Probability · Mathematics 2007-05-23 Robin Pemantle