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Related papers: Independence densities of hypergraphs

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The independence gap of a graph was introduced by Ekim et al. (2018) as a measure of how far a graph is from being well-covered. It is defined as the difference between the maximum and minimum size of a maximal independent set. We…

Combinatorics · Mathematics 2018-12-14 Tınaz Ekim , Didem Gözüpek , Ademir Hujdurović , Martin Milanič

Given an integer $k\geq 3$ and an initial $k-1$ isolated vertices, an {\em antiregular $k$-hypergraph} is constructed by alternatively adding an isolated vertex (connected to no other vertices) or a dominating vertex (connected to every…

Combinatorics · Mathematics 2023-03-03 Erchuan Zhang

Given a family $\mathcal{I}$ of independent sets in a graph, a rainbow independent set is an independent set $I$ such that there is an injection $\phi\colon I\to \mathcal{I}$ where for each $v\in I$, $v$ is contained in $\phi(v)$. Aharoni,…

Combinatorics · Mathematics 2021-04-12 Jinha Kim , Minki Kim , O-joung Kwon

A well-known result of Ajtai et al. from 1982 states that every $k$-graph $H$ on $n$ vertices, with girth at least five, and average degree $t^{k-1}$ contains an independent set of size $c n (\log t)^{1/(k-1)}/t$ for some $c>0$. In this…

Combinatorics · Mathematics 2023-01-19 Vojtěch Rödl , Marcelo Sales , Yi Zhao

Let $G$ be a triangle-free graph with $n$ vertices and average degree $t$. We show that $G$ contains at least \[ e^{(1-n^{-1/12})\frac{1}{2}\frac{n}{t}\ln t (\frac{1}{2}\ln t-1)} \] independent sets. This improves a recent result of the…

Combinatorics · Mathematics 2019-02-20 Jeff Cooper , Kunal Dutta , Dhruv Mubayi

Let $G=(V,E)$ be a simple graph. A set $I\subseteq V$ is an independent set, if no two of its members are adjacent in $G$. The $k$-independent graph of $G$, $I_k (G)$, is defined to be the graph whose vertices correspond to the independent…

Combinatorics · Mathematics 2020-01-03 Davood Fatehi , Saeid Alikhani , Abdul Jalil M. Khalaf

The independence polynomial $i(G,x)$ of a graph $G$ is the generating function of the numbers of independent sets of each size. A graph of order $n$ is very well-covered if every maximal independent set has size $n/2$. Levit and Mandrescu…

Combinatorics · Mathematics 2017-09-26 Jason I. Brown , Ben Cameron

An independent set $I_c$ is a \textit{critical independent set} if $|I_c| - |N(I_c)| \geq |J| - |N(J)|$, for any independent set $J$. The \textit{critical independence number} of a graph is the cardinality of a maximum critical independent…

Combinatorics · Mathematics 2009-12-14 Craig Eric Larson

We show that if a sequence of dense graphs has the property that for every fixed graph F, the density of copies of F in these graphs tends to a limit, then there is a natural ``limit object'', namely a symmetric measurable 2-variable…

Combinatorics · Mathematics 2007-05-23 Laszlo Lovasz , Balazs Szegedy

We prove a tight upper bound on the independence polynomial (and total number of independent sets) of cubic graphs of girth at least 5. The bound is achieved by unions of the Heawood graph, the point/line incidence graph of the Fano plane.…

Combinatorics · Mathematics 2018-04-12 Guillem Perarnau , Will Perkins

Notions of freedom and independence for hypergraphs of models of a theory are defined. Properties of these notions and their applications to some natural classes of theories are studied.

Logic · Mathematics 2018-02-28 Beibut Kulpeshov , Sergey Sudoplatov

This paper generalizes and unifies the existing spectral bounds on the $k$-independence number of a graph, which is the maximum size of a set of vertices at pairwise distance greater than $k$. The previous bounds known in the literature…

Combinatorics · Mathematics 2018-08-28 A. Abiad , G. Coutinho , M. A. Fiol

An independent $[1,k]$-set $S$ in a graph $G$ is a dominating set which is independent and such that every vertex not in $S$ has at most $k$ neighbors in it. The existence of such sets is not guaranteed in every graph and trees having an…

Combinatorics · Mathematics 2015-12-01 Sahar Aleid , Jose Caceres , Maria Luz Puertas

The independence numbers of powers of graphs have been long studied, under several definitions of graph products, and in particular, under the strong graph product. We show that the series of independence numbers in strong powers of a fixed…

Information Theory · Computer Science 2016-11-17 Noga Alon , Eyal Lubetzky

A maximal independent set in a graph $G$ is an independent set that cannot be extended to a larger independent set by adding any vertex from $G$. This paper investigates the problem of determining the maximum number of maximal independent…

Combinatorics · Mathematics 2025-06-02 Yongtang Shi , Jianhua Tu , Ziyuan Wang

We develop a notion of containment for independent sets in hypergraphs. For every $r$-uniform hypergraph $G$, we find a relatively small collection $C$ of vertex subsets, such that every independent set of $G$ is contained within a member…

Combinatorics · Mathematics 2014-12-01 David Saxton , Andrew Thomason

The independence number $\alpha(H)$ of a hypergraph $H$ is the maximum cardinality of a set of vertices of $H$ that does not contain an edge of $H$. Generalizing Shearer's classical lower bound on the independence number of triangle-free…

Combinatorics · Mathematics 2015-07-16 Piotr Borowiecki , Michael Gentner , Christian Löwenstein , Dieter Rautenbach

An independent set in a graph G is a set of vertices no two of which are joined by an edge. A vertex-weighted graph associates a weight with every vertex in the graph. A vertex-weighted graph G is called a unique independence…

Computational Complexity · Computer Science 2009-07-02 Farzad Didehvar , Ali D. Mehrabi , Fatemeh Raee B

P. Erd\H{o}s [On extremal problems of graphs and generalized graphs, Israel Journal of Mathematics 2 (1964), 183-190] characterised those hypergraphs $F$ that have to appear in any sufficiently large hypergraph $H$ of positive density. We…

Combinatorics · Mathematics 2019-01-30 Christian Reiher , Vojtěch Rödl , Mathias Schacht

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