English
Related papers

Related papers: Treewidth and gonality of glued grid graphs

200 papers

To each link $L$ in $S^3$ we associate a collection of certain labelled directed trees, called width trees. We interpret some classical and new topological link invariants in terms of these width trees and show how the geometric structure…

Geometric Topology · Mathematics 2021-09-28 Qidong He , Scott A. Taylor

We study the recently introduced boolean-width of graphs. Our structural results are as follows. Firstly, we show that almost surely the boolean-width of a random graph on $n$ vertices is $O(\log^2 n)$, and it is easy to find the…

Combinatorics · Mathematics 2009-08-20 Y. Rabinovich , J. A. Telle

Given a finite planar graph, a grove is a spanning forest in which every component tree contains one or more of a specified set of vertices (called nodes) on the outer face. For the uniform measure on groves, we compute the probabilities of…

Probability · Mathematics 2011-06-30 Richard W. Kenyon , David B. Wilson

Let $\mathbf G$ be a graphing, that is a Borel graph defined by $d$ measure preserving involutions. We prove that if $\mathbf G$ is {\em treeable} then it arises as the local limit of some sequence $(G_n)_{n\in\mathbb{N}}$ of graphs with…

Combinatorics · Mathematics 2016-01-22 Lucas Hosseini , Patrice Ossona de Mendez

In this paper, we give a very simple proof that Treewidth is NP-complete; this proof also shows NP-completeness on the class of co-bipartite graphs. We then improve the result by Bodlaender and Thilikos from 1997 that Treewidth is…

Bounded infinite graphs are defined on the basis of natural physical requirements. When specialized to trees this definition leads to a natural conjecture that the average connectivity dimension of bounded trees cannot exceed two. We verify…

Condensed Matter · Physics 2009-11-07 Claudio Destri , Luca Donetti

A shelling of a graph, viewed as an abstract simplicial complex that is pure of dimension 1, is an ordering of its edges such that every edge is adjacent to some other edges appeared previously. In this paper, we focus on complete bipartite…

Combinatorics · Mathematics 2021-02-11 Yibo Gao , Junyao Peng

Let Q_n be the graph of n times n times n cube with all non-decreasing diagonals (including the facial ones) in its constituent unit cubes. Suppose that a subset S of V(Q_n) separates the left side of the cube from the right side. We show…

Combinatorics · Mathematics 2015-12-22 Eli Berger , Zdenek Dvorak , Sergey Norin

We consider a weighted counting problem on matchings, denoted $\textrm{PrMatching}(\mathcal{G})$, on an arbitrary fixed graph family $\mathcal{G}$. The input consists of a graph $G\in \mathcal{G}$ and of rational probabilities of existence…

Computational Complexity · Computer Science 2023-01-10 Antoine Amarilli , Mikaël Monet

We investigate a relaxation of the notion of treewidth-fragility, namely tree-independence-number-fragility. In particular, we obtain polynomial-time approximation schemes for independent packing problems on fractionally…

Data Structures and Algorithms · Computer Science 2025-04-23 Esther Galby , Andrea Munaro , Shizhou Yang

The distribution of distances in the star graph $ST_n$, ($1<n\in\Z$), is established, and subsequently a threaded binary tree is obtained that realizes an orientation of $ST_n$ whose levels are given by the distances to the identity…

Combinatorics · Mathematics 2010-11-16 Italo J. Dejter

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 study the inertia of distance matrices of weighted graphs. Our novel congruence-based proof of the inertia of weighted trees extends to a proof for the inertia of weighted unicyclic graphs whose cycle is a triangle. Partial results are…

Combinatorics · Mathematics 2023-04-26 Jeffrey Cheng , Ian Malcolm Johnson McInnis , Matthew Yee

Gurski and Wanke showed that a graph class C has bounded tree-width if and only if its associated class of directed line graphs has bounded clique-width. Inevitably -- asking whether this relationship lifts to directed graphs -- we…

Combinatorics · Mathematics 2025-02-24 Benjamin Merlin Bumpus , Kitty Meeks , William Pettersson

We present a constraint model for the problem of producing a tree decomposition of a graph. The inputs to the model are a simple graph G, the number of nodes in the desired tree decomposition and the maximum cardinality of each node in that…

Discrete Mathematics · Computer Science 2019-08-08 Benjamin Bumpus , Patrick Prosser , James Trimble

By a well known result the treewidth of k-outerplanar graphs is at most 3k-1. This paper gives, besides a rigorous proof of this fact, an algorithmic implementation of the proof, i.e. it is shown that, given a k-outerplanar graph G, a tree…

Data Structures and Algorithms · Computer Science 2013-01-25 Ioannis Katsikarelis

In this paper we compare and illustrate the algorithmic use of graphs of bounded tree-width and graphs of bounded clique-width. For this purpose we give polynomial time algorithms for computing the four basic graph parameters independence…

Data Structures and Algorithms · Computer Science 2008-12-18 Frank Gurski

The degree sequence of a graph is a numerical method to characterize the properties of graphs. Generalized forms of degree sequences exist for complete graphs and complete graphs. Nikolopolus et al. characterized the number of spanning…

Combinatorics · Mathematics 2019-06-17 Joshua Steier

There are hierarchical characteristics in the network and how to effectively reveal the hierarchical characteristics in the network is a problem in the research of network structure. If a node is assigned to the community to which it…

Social and Information Networks · Computer Science 2020-03-06 Shun Fu , Ji Xu

We develop a gauge theory or theory of bundles and connections on them at the level of braids and tangles. Extending recent algebraic work, we provide now a fully diagrammatic treatment of principal bundles, a theory of global gauge…

q-alg · Mathematics 2008-02-03 S. Majid