Results 91 to 100 of about 11,596 (195)

The Turán problem for hypergraphs of fixed size [PDF]

We obtain a general bound on the Turán density of a hypergraph in terms of the number of edges that it contains. If F is an r-uniform hypergraph with f edges we show that [pi](F) =3 and f->[infinity]
Keevash, Peter
core  

Consistency of Spectral Hypergraph Partitioning under Planted Partition Model

Hypergraph partitioning lies at the heart of a number of problems in machine learning and network sciences. Many algorithms for hypergraph partitioning have been proposed that extend standard approaches for graph partitioning to the case of hypergraphs ...
Dukkipati, Ambedkar, Ghoshdastidar, Debarghya   +1 more
core   +2 more sources

Hypergraphs with Pendant Paths are not Chromatically Unique

Discussiones Mathematicae Graph Theory, 2014
In this note it is shown that every hypergraph containing a pendant path of length at least 2 is not chromatically unique. The same conclusion holds for h-uniform r-quasi linear 3-cycle if r ≥ 2.
Tomescu Ioan
doaj   +1 more source

Hypergraph Representation via Axis-Aligned Point-Subspace Cover [PDF]

Discrete Mathematics & Theoretical Computer Science
We propose a new representation of $k$-partite, $k$-uniform hypergraphs, that is, a hypergraph with a partition of vertices into $k$ parts such that each hyperedge contains exactly one vertex of each type; we call them $k$-hypergraphs for short.
Oksana Firman, Joachim Spoerhase
doaj   +1 more source

Matchings in 3-uniform hypergraphs

Journal of Combinatorial Theory, Series B, 2013
We determine the minimum vertex degree that ensures a perfect matching in a 3-uniform hypergraph. More precisely, suppose that H is a sufficiently large 3-uniform hypergraph whose order n is divisible by 3. If the minimum vertex degree of H is greater than \binom{n-1}{2}-\binom{2n/3}{2}, then H contains a perfect matching.
Daniela Kühn, Deryk Osthus, Andrew Treglown   +2 more
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Linear trees in uniform hypergraphs

European Journal of Combinatorics, 2014
Given a tree T on v vertices and an integer k exceeding one. One can define the k-expansion T^k as a k-uniform linear hypergraph by enlarging each edge with a new, distinct set of (k-2) vertices. Then T^k has v+ (v-1)(k-2) vertices. The aim of this paper is to show that using the delta-system method one can easily determine asymptotically the size of ...
openaire   +2 more sources

Partitioning 3-uniform hypergraphs

Journal of Combinatorial Theory, Series B, 2012
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Jie Ma 0002, Xingxing Yu
openaire   +1 more source

On the Maximum Estrada Index of 3-Uniform Linear Hypertrees

The Scientific World Journal, 2014
For a simple hypergraph H on n vertices, its Estrada index is defined as EE(H)=∑i=1n‍eλi, where λ1,λ2,…,λn are the eigenvalues of its adjacency matrix. In this paper, we determine the unique 3-uniform linear hypertree with the maximum Estrada index.
Faxu Li, Liang Wei, Jinde Cao, Feng Hu, Haixing Zhao   +4 more
doaj   +1 more source

Wickets in 3-uniform hypergraphs

Discrete Mathematics
In these notes, we consider a Turán-type problem in hypergraphs. What is the maximum number of edges if we forbid a subgraph? Let $H_n^{(3)}$ be a 3-uniform linear hypergraph, i.e. any two edges have at most one vertex common. A special hypergraph, called {\em wicket}, is formed by three rows and two columns of a $3 \times 3$ point matrix.
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The Largest Laplacian and Signless Laplacian H-Eigenvalues of a Uniform Hypergraph

In this paper, we show that the largest Laplacian H-eigenvalue of a $k$-uniform nontrivial hypergraph is strictly larger than the maximum degree when $k$ is even. A tight lower bound for this eigenvalue is given.
Hu, Shenglong, Qi, Liqun, Xie, Jinshan
core   +1 more source