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Related papers: Independence densities of hypergraphs

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By an independent set in a simple graph $G$, we mean a set of pairwise non-adjacent vertices in $G$. The independence polynomial of $G$ is defined as $I_G(z)=a_0 + a_1 z + a_2 z^2+\cdots+a_\alpha z^{\alpha}$, where $a_i$ is the number of…

Combinatorics · Mathematics 2025-05-28 Garima Khetawat , Moumita Manna , Tarakanta Nayak

Amongst $d$-regular $r$-uniform hypergraphs on $n$ vertices, which ones have the largest number of independent sets? While the analogous problem for graphs (originally raised by Granville) is now well-understood, it is not even clear what…

Combinatorics · Mathematics 2020-02-25 Jozsef Balogh , Bela Bollobas , Bhargav Narayanan

We presents an independence relation on sets, one can define dimension by it, assuming that we have an abstract elementary class with a forking notion that satisfies the axioms of a good frame minus stability.

Logic · Mathematics 2011-05-19 Adi Jarden , Alon Sitton

For a positive integer $k$ and a graph $H$ on $k$ vertices, we are interested in the inducibility of $H$, denoted $\mathrm{ind}(H)$, which is defined as the maximum possible probability that choosing $k$ vertices uniformly at random from a…

Combinatorics · Mathematics 2024-11-27 Richard Ueltzen

Given a countable graph, we say a set $A$ of its vertices is \emph{universal} if it contains every countable graph as an induced subgraph, and $A$ is \emph{weakly universal} if it contains every finite graph as an induced subgraph. We show…

Combinatorics · Mathematics 2017-02-24 Will Brian

A graph is $H$-free if it does not contain an induced subgraph isomorphic to $H$. For every integer $k$ and every graph $H$, we determine the computational complexity of $k$-Edge Colouring for $H$-free graphs.

Data Structures and Algorithms · Computer Science 2018-10-11 Esther Galby , Paloma T. Lima , Daniel Paulusma , Bernard Ries

Given two graphs $H_1$ and $H_2$, a graph is $(H_1,H_2)$-free if it contains no induced subgraph isomorphic to $H_1$ nor $H_2$. A graph $G$ is $k$-vertex-critical if every proper induced subgraph of $G$ has chromatic number less than $k$,…

Combinatorics · Mathematics 2024-03-12 Wen Xia , Jorik Jooken , Jan Goedgebeur , Shenwei Huang

An independent set in a graph is a set of pairwise non-adjacent vertices, and a(G) is the size of a maximum independent set in the graph G. If s_{k} is the number of independent sets of cardinality k in G, then…

Discrete Mathematics · Computer Science 2013-03-12 Vadim E. Levit , Eugen Mandrescu

The \emph{regular independence number}, introduced by Albertson and Boutin in 1990, is the maximum cardinality of an independent set of $G$ in which all vertices have equal degree in $G$. Recently, Caro, Hansberg and Pepper introduced the…

Combinatorics · Mathematics 2015-09-01 Zhiwei Guo , Haixing Zhao , Hongjian Lai , Yaping Mao

A vertex subset $W\subseteq V$ of the graph $G=(V,E)$ is an independent dominating set if every vertex in $V\backslash W$ is adjacent to at least one vertex in $W$ and the vertices of $W$ are pairwise non-adjacent. The independent…

Combinatorics · Mathematics 2016-02-29 Markus Dod

For a set $S$ of vertices of a graph $G$, a vertex $u$ in $V(G)\setminus S$, and a vertex $v$ in $S$, let ${\rm dist}_{(G,S)}(u,v)$ be the distance of $u$ and $v$ in the graph $G-(S\setminus \{ v\})$. Dankelmann et al. (Domination with…

Combinatorics · Mathematics 2016-05-20 Simon Jäger , Dieter Rautenbach

An independent set in a simple graph $G$ is a set of pairwise non-adjacent vertices in $G$. The independence polynomial of $G$, denoted by $I_G$ is defined as $1 + a_1 z + a_2 z^2+\cdots+a_d z^{d}$, where $a_i$ denotes the number of…

Combinatorics · Mathematics 2025-08-07 Moumita Manna , Tarakanta Nayak

We construct several pairwise-incomparable bounds on the projective dimensions of edge ideals. Our bounds use combinatorial properties of the associated graphs; in particular we draw heavily from the topic of dominating sets. Through…

Commutative Algebra · Mathematics 2011-10-25 Hailong Dao , Jay Schweig

The enumeration of independent sets of regular graphs is of interest in statistical mechanics, as it corresponds to the solution of hard-particle models. In 2004, it was conjectured by Fendleyet al. that for some rectangular grids, with…

Combinatorics · Mathematics 2008-10-31 Mireille Bousquet-Mélou , Svante Linusson , Eran Nevo

There has been a great deal of attention recently to graphs whose vertex set is a group, defined using the group structure. (The commuting graph, where two elements are joined if they commute, is the oldest and most famous example.) The…

Combinatorics · Mathematics 2026-02-03 Peter J. Cameron

Let $\sigma$ be a partition of the positive integer $r$. A $\sigma$-hypergraph $H=H(n,r,q|\sigma)$ is an $r$-uniform hypergraph on $nq$ vertices which are partitioned into $n$ classes $V_1, V_2, \ldots, V_n$ each containing $q$ vertices. An…

Combinatorics · Mathematics 2014-05-02 Yair Caro , Josef Lauri , Christina Zarb

In this note we prove a large deviation bound on the sum of random variables with the following dependency structure: there is a dependency graph $G$ with a bounded chromatic number, in which each vertex represents a random variable.…

Probability · Mathematics 2007-06-13 Ronen Gradwohl , Amir Yehudayoff

In this paper, we consider the problem of finding weak independent sets in a distributed network represented by a hypergraph. In this setting, each edge contains a set of r vertices rather than simply a pair, as in a standard graph. A…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-11-21 Duncan Adamson , Will Rosenbaum , Paul G. Spirakis

Linek's 1989 problem asks whether the numbers of independent sets of trees avoid infinitely many positive integers. We show that the set of natural numbers realized as the number of independent sets of a tree has a lower growth exponent of…

Combinatorics · Mathematics 2026-04-22 Swee Hong Chan , Steven Heilman , Greta Panova

The graph polynomial for the number of independent sets of size $k$ in a general undirected graph is shown to be equal to an elementary symmetric polynomial of the vertex monomials, which are determined by the edges incident at the…

Combinatorics · Mathematics 2023-12-12 R. L. Streit