Results 21 to 30 of about 622 (164)

Saturated r-uniform hypergraphs

open access: yesDiscrete Mathematics, 1991
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Erdős, Paul   +2 more
openaire   +1 more source

Spectra of uniform hypergraphs

open access: yesLinear Algebra and its Applications, 2012
We present a spectral theory of hypergraphs that closely parallels Spectral Graph Theory. A number of recent developments building upon classical work has led to a rich understanding of "hyperdeterminants" of hypermatrices, a.k.a. multidimensional arrays.
Cooper, Joshua, Dutle, Aaron
openaire   +3 more sources

The Lagrangian Density of {123, 234, 456} and the Turán Number of its Extension

open access: yesDiscussiones Mathematicae Graph Theory, 2021
Given a positive integer n and an r-uniform hypergraph F, the Turán number ex(n, F ) is the maximum number of edges in an F -free r-uniform hypergraph on n vertices.
Chen Pingge, Liang Jinhua, Peng Yuejian
doaj   +1 more source

Turán Problems on Non-Uniform Hypergraphs [PDF]

open access: yesThe Electronic Journal of Combinatorics, 2014
A non-uniform hypergraph $H=(V,E)$ consists of a vertex set $V$ and an edge set $E\subseteq 2^V$; the edges in $E$ are not required to all have the same cardinality. The set of all cardinalities of edges in $H$ is denoted by $R(H)$, the set of edge types.
Johnston, J. Travis, Lu, Linyuan
openaire   +3 more sources

High Girth Hypergraphs with Unavoidable Monochromatic or Rainbow Edges

open access: yesDiscussiones Mathematicae Graph Theory, 2022
A classical result of Erdős and Hajnal claims that for any integers k, r, g ≥ 2 there is an r-uniform hypergraph of girth at least g with chromatic number at least k.
Axenovich Maria, Karrer Annette
doaj   +1 more source

A sharp upper bound on the spectral radius of a nonnegative k-uniform tensor and its applications to (directed) hypergraphs

open access: yesJournal of Inequalities and Applications, 2020
In this paper, we obtain a sharp upper bound on the spectral radius of a nonnegative k-uniform tensor and characterize when this bound is achieved. Furthermore, this result deduces the main result in [X. Duan and B.
Chuang Lv, Lihua You, Xiao-Dong Zhang
doaj   +1 more source

Nearly Perfect Matchings in Uniform Hypergraphs

open access: yesSIAM Journal on Discrete Mathematics, 2021
In this paper, we study degree conditions for the existence of large matchings in uniform hypergraphs. We prove that for integers $k,l,n$ with $k\ge 3$, $k/2{n-l\choose k-l}-{(n-l)-(\lceil n/k \rceil-2)\choose 2}$, then $H$ has a matching covering all but a constant number of vertices.
Lu, Hongliang   +2 more
openaire   +2 more sources

On Lagrangians of r-uniform hypergraphs [PDF]

open access: yesJournal of Combinatorial Optimization, 2013
A remarkable connection between the order of a maximum clique and the Lagrangian of a graph was established by Motzkin and Straus in [7]. This connection and its extensions were successfully employed in optimization to provide heuristics for the maximum clique number in graphs. It has been also applied in spectral graph theory.
Peng, Yuejian   +2 more
openaire   +3 more sources

The Existence of Quasi Regular and Bi-Regular Self-Complementary 3-Uniform Hypergraphs

open access: yesDiscussiones Mathematicae Graph Theory, 2016
A k-uniform hypergraph H = (V ;E) is called self-complementary if there is a permutation σ : V → V , called a complementing permutation, such that for every k-subset e of V , e ∈ E if and only if σ(e) ∉ E. In other words, H is isomorphic with H′ = (V ; V(
Kamble Lata N.   +2 more
doaj   +1 more source

Cyclic Partitions of Complete and Almost Complete Uniform Hypergraphs

open access: yesDiscussiones Mathematicae Graph Theory, 2022
We consider cyclic partitions of the complete k-uniform hypergraph on a finite set V, minus a set of s edges, s ≥ 0. An s-almost t-complementary k-hypergraph is a k-uniform hypergraph with vertex set V and edge set E for which there exists a permutation ...
Dilbarjot, Gosselin Shonda Dueck
doaj   +1 more source

Home - About - Disclaimer - Privacy