English
Related papers

Related papers: Maximal independent sets and separating covers

200 papers

Let $Q_n$ be the $n$-dimensional Hamming cube and $N=2^n$. We prove that the number of maximal independent sets in $Q_n$ is asymptotically \[2n2^{N/4},\] as was conjectured by Ilinca and the first author in connection with a question of…

Combinatorics · Mathematics 2019-09-12 Jeff Kahn , Jinyoung Park

We show that, for any n-vertex graph G and integer parameter k, there are at most 3^{4k-n}4^{n-3k} maximal independent sets I \subset G with |I| <= k, and that all such sets can be listed in time O(3^{4k-n} 4^{n-3k}). These bounds are tight…

Data Structures and Algorithms · Computer Science 2007-05-23 David Eppstein

Given a graph G, let Q(G) denote the collection of all independent (edge-free) sets of vertices in G. We consider the problem of determining the size of a largest antichain in Q(G). When G is the edge-less graph, this problem is resolved by…

Combinatorics · Mathematics 2013-10-08 Victor Falgas-Ravry

Nielsen proved that the maximum number of maximal independent sets (MIS's) of size $k$ in an $n$-vertex graph is asymptotic to $(n/k)^k$, with the extremal construction a disjoint union of $k$ cliques with sizes as close to $n/k$ as…

Combinatorics · Mathematics 2021-08-17 Xiaoyu He , Jiaxi Nie , Sam Spiro

An independent transversal in a multipartite graph is an independent set that intersects each part in exactly one vertex. We show that for every even integer $r\ge 2$, there exist $c_r>0$ and $n_0$ such that every $r$-partite graph with…

Combinatorics · Mathematics 2025-04-08 Yantao Tang , Yi Zhao

The independence polynomial of a graph is the generating polynomial for the number of independent sets of each size and its roots are called independence roots. We bound the maximum modulus, $\mbox{maxmod}(n)$, of an independence root over…

Combinatorics · Mathematics 2018-12-27 Jason I. Brown , Ben Cameron

Fix a positive integer $n$ and consider the bipartite graph whose vertices are the $3$-element subsets and the $2$-element subsets of $[n]=\{1,2,\dots,n\}$, and there is an edge between $A$ and $B$ if $A\subset B$. We prove that the…

Combinatorics · Mathematics 2024-06-25 Thomas Kalinowski , Uwe Leck

We study the problem of maximizing the number of independent sets in $n$-vertex $k$-chromatic $\ell$-connected graphs. First we consider maximizing the total number of independent sets in such graphs with $n$ sufficiently large, and for…

Combinatorics · Mathematics 2019-07-10 John Engbers , Lauren Keough , Taylor Short

Sparse-dense partitions was introduced by Feder, Hell, Klein, and Motwani [STOC 1999, SIDMA 2003] as a tool to solve partitioning problems. In this paper, the following result concerning independent sets in graphs having sparse-dense…

Discrete Mathematics · Computer Science 2022-08-10 Uéverton S. Souza

We give a very short and simple proof of Zykov's generalization of Tur\'{a}n's theorem, which implies that the number of maximum independent sets of a graph of order $n$ and independence number $\alpha$ with $\alpha<n$ is at most…

Combinatorics · Mathematics 2018-05-08 Elena Mohr , Dieter Rautenbach

The goal of this paper is to obtain quantitative results on the number and on the size of maximal independent sets and maximal matchings in several block-stable graph classes that satisfy a proper sub-criticality condition. In particular we…

Combinatorics · Mathematics 2020-12-29 Michael Drmota , Lander Ramos , Clément Requilé , Juanjo Rué

The main purpose of this paper is to prove the uniqueness of a graph attaining the maximum of the number of independent sets over all $k$-regular graphs on $n$ vertices for $2k|n$.

Combinatorics · Mathematics 2016-03-01 Alexei Dmitriev , Alex Dainiak

The maximum independent set problem is known to be NP-hard in the class of subcubic graphs, i.e. graphs of vertex degree at most 3. We present a polynomial-time solution in a subclass of subcubic graphs generalizing several previously known…

Data Structures and Algorithms · Computer Science 2018-10-26 Ararat Harutyunyan , Michael Lampis , Vadim Lozin , Jérôme Monnot

Settling Kahn's conjecture (2001), we prove the following upper bound on the number $i(G)$ of independent sets in a graph $G$ without isolated vertices: \[ i(G) \le \prod_{uv \in E(G)} i(K_{d_u,d_v})^{1/(d_u d_v)}, \] where $d_u$ is the…

Combinatorics · Mathematics 2019-08-19 Ashwin Sah , Mehtaab Sawhney , David Stoner , Yufei Zhao

We introduce methods to count and enumerate all maximal independent, all maximum independent sets, and all independent sets in threshold graphs and k-threshold graphs. Within threshold graphs and k-threshold graphs independent sets…

Data Structures and Algorithms · Computer Science 2017-10-26 Frank Gurski , Carolin Rehs

We determine the largest subset $A\subseteq \{1,\dotsc,n\}$ such that for all $a,b\in A$, the product $ab$ is not squarefree. Specifically, the maximum size is achieved by the complement of the odd squarefree numbers. This resolves a…

Combinatorics · Mathematics 2025-07-04 Boris Alexeev , Dustin G. Mixon , Will Sawin

In this paper, connections between independent sets and the variety of mutual-visibility sets are studied. It is proved that every outer mutual-visibility set of a graph is independent if and only if the graph is distance edge-critical.…

Combinatorics · Mathematics 2026-03-02 Jing Tian , Csilla Bujtás , Sandi Klavžar

A maximal independent set is an independent set that is not a subset of any other independent set. It is also the key problem of mathematics, computer science, and other fields. A counting problem is a type of computational problem that…

Computational Complexity · Computer Science 2024-09-16 Hao Zhang , Tonghua Su

Extremal problems concerning the number of independent sets or complete subgraphs in a graph have been well studied in recent years. Cutler and Radcliffe proved that among graphs with $n$ vertices and maximum degree at most $r$, where $n =…

Combinatorics · Mathematics 2019-06-11 R. Kirsch , A. J. Radcliffe

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