English
Related papers

Related papers: The Independence Number of the Orthogonality Graph…

200 papers

The independence number of a tree decomposition is the maximum of the independence numbers of the subgraphs induced by its bags. The tree-independence number of a graph is the minimum independence number of a tree decomposition of it.…

Data Structures and Algorithms · Computer Science 2025-09-11 Clément Dallard , Fedor V. Fomin , Petr A. Golovach , Tuukka Korhonen , Martin Milanič

In 2011, Henning, L\"{o}wenstein, and Rautenbach observed that the domination number of a graph is bounded from above by the product of the packing number and the maximum degree of the graph. We prove a stronger statement in subcubic…

Combinatorics · Mathematics 2023-07-12 Eun-Kyung Cho , Minki Kim

We study the free product of rooted graphs and its various decompositions using quantum probabilistic methods. We show that the free product of rooted graphs is canonically associated with free independence, which completes the proof of the…

Combinatorics · Mathematics 2014-07-25 Luigi Accardi , Romuald Lenczewski , Rafal Salapata

Let G be a graph. The independence-domination number is the maximum over all independent sets I in G of the minimal number of vertices needed to dominate I. In this paper we investigate the computational complexity of independence…

Discrete Mathematics · Computer Science 2013-04-25 Wing-Kai Hon , Ton Kloks , Hsiang Hsuan Liu , Sheung-Hung Poon , Yue-Li Wang

Given a finite, simple graph $G$, the independent bondage number of $G$ is the minimum size of an edge set such that its deletion results in a graph with strictly larger independent domination number than that of $G$. While the bondage…

Combinatorics · Mathematics 2025-10-15 E. G. K. M. Gamlath , Andrew Pham , Bing Wei

A hexagonal patch is a plane graph in which inner faces have length 6, inner vertices have degree 3, and boundary vertices have degree 2 or 3. We consider the following counting problem: given a sequence of twos and threes, how many…

Discrete Mathematics · Computer Science 2009-07-15 Paul Bonsma , Felix Breuer

A graph is inductive $k$-independent if there exists and ordering of its vertices $v_{1},...,v_{n}$ such that $\alpha(G[N(v_{i})\cap V_{i}])\leq k $ where $N(v_{i})$ is the neighborhood of $v_{i}$, $V_{i}=\{v_{i},...,v_{n}\}$ and $\alpha$…

Discrete Mathematics · Computer Science 2017-09-21 George Manoussakis

We revisit the problem of determining the independent domination number in hypercubes for which the known upper bound is still not tight for general dimensions. We present here a constructive method to build an independent dominating set…

Discrete Mathematics · Computer Science 2022-05-16 Debabani Chowdhury , Debesh K. Das , Bhargab B. Bhattacharya

The independence number of a hypergraph H is the size of a largest set of vertices containing no edge of H. In this paper, we prove new sharp bounds on the independence number of n-vertex (r+1)-uniform hypergraphs in which every r-element…

Combinatorics · Mathematics 2011-06-17 Alexander Kostochka , Dhruv Mubayi , Jacques Versatraete

The $k^{\text{th}}$ power of a graph $G=(V,E)$, $G^k$, is the graph whose vertex set is $V$ and in which two distinct vertices are adjacent if and only if their distance in $G$ is at most $k$. This article proves various eigenvalue bounds…

Combinatorics · Mathematics 2020-10-27 Aida Abiad , Gabriel Coutinho , Miquel Angel Fiol , Bruno Nogueira , Sjanne Zeijlemaker

A set is called r-independent, if every two vertices of it are in distance greater then r. In the r-independent set problem with parameter k, we ask whether in a given graph G there exists an r-independent set of size k. In this work we…

Data Structures and Algorithms · Computer Science 2019-12-03 Grzegorz Fabiański

The independence density of a finite hypergraph is the probability that a subset of vertices, chosen uniformly at random contains no hyperedges. Independence densities can be generalized to countable hypergraphs using limits. We show that,…

Combinatorics · Mathematics 2016-04-20 Paul Balister , Béla Bollobás , Karen Gunderson

Two independent sets of a graph are adjacent if they differ on exactly one vertex (i.e. we can transform one into the other by adding or deleting a vertex). Let $k$ be an integer. We consider the reconfiguration graph $TAR_k(G)$ on the set…

Discrete Mathematics · Computer Science 2014-06-06 Marthe Bonamy , Nicolas Bousquet

Let $i_t(G)$ be the number of independent sets of size $t$ in a graph $G$. Alavi, Erd\H{o}s, Malde and Schwenk made the conjecture that if $G$ is a tree then the independent set sequence $\{i_t(G)\}_{t\geq 0}$ of $G$ is unimodal; Levit and…

Combinatorics · Mathematics 2012-06-27 David Galvin

We obtain new lower bounds for the independence number of $K_r$-free graphs and linear $k$-uniform hypergraphs in terms of the degree sequence. This answers some old questions raised by Caro and Tuza \cite{CT91}. Our proof technique is an…

Combinatorics · Mathematics 2011-02-25 Kunal Dutta , Dhruv Mubayi , C. R. Subramanian

A theorem of Hoffman gives an upper bound on the independence ratio of regular graphs in terms of the minimum $\lambda_{\min}$ of the spectrum of the adjacency matrix. To complement this result we use random eigenvectors to gain lower…

Probability · Mathematics 2016-08-11 Viktor Harangi , Bálint Virág

In this paper, we study the independence polynomial $P_G(x)$ of a finite simple graph $G$, with emphasis on the evaluation at $x=-1$, symmetry, and its connection with the $h$-polynomial of the edge ideal of $G$. For big star graphs, we…

Combinatorics · Mathematics 2026-03-18 Takayuki Hibi , Selvi Kara , Dalena Vien

Every $n$-vertex planar triangle-free graph with maximum degree at most $3$ has an independent set of size at least $\frac{3}{8}n$. This was first conjectured by Albertson, Bollob\'as and Tucker, and was later proved by Heckman and Thomas.…

Combinatorics · Mathematics 2020-07-15 Wouter Cames van Batenburg , Jan Goedgebeur , Gwenaël Joret

This paper addresses the challenge of spectral analysis and structural investigation for graphs that are not distance-regular, where computing the spectrum using standard methods based on equitable and orbit partitions can be complex. Our…

Combinatorics · Mathematics 2025-11-26 Ali Zafari , Saeid Alikhani

Independence complexes of circle graphs are purely combinatorial objects. However, when constructed from some diagram of a link $L$, they reveal topological properties of $L$, more specifically, of its Khovanov homology. We analyze the…