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papers

Publications (8)

math.CO2012

Specified Intersections

Dhruv Mubayi, Vojtech Rodl

Let M be a subset of {0, .., n} and F be a family of subsets of an n element set such that the size of A intersection B is in M for every A, B in F. Suppose that l is the maximum n…

math.CO2015

Hypergraph Ramsey numbers: tight cycles versus cliques

Dhruv Mubayi, Vojtech Rodl

For $s \geq 4$ , the 3-uniform tight cycle $C_{s}^{3}$ has vertex set corresponding to $s$ distinct points on a circle and edge set given by the $s$ cyclic intervals of three consecutive…

math.CO2016

The Minimum Number of Edges in Uniform Hypergraphs with Property O

Dwight Duffus, Bill Kay, Vojtech Rodl

An oriented k-uniform hypergraph (a family of ordered k-sets) has the ordering property (or Property O) if for every linear order of the vertex set, there is some edge oriented con…

math.CO2012

Large matchings in uniform hypergraphs and the conjectures of Erdos and Samuels

Noga Alon, Peter Frankl, Hao Huang +3

In this paper we study conditions which guarantee the existence of perfect matchings and perfect fractional matchings in uniform hypergraphs. We reduce this problem to an old conje…

math.CO2025

Subgraphs with a positive minimum semidegree in digraphs with large outdegree

Andrzej Grzesik, Vojtech Rodl, Jan Volec

We prove that every $n$ -vertex directed graph $G$ with the minimum outdegree $I^´^{+} (G) = d$ contains a subgraph $H$ satisfying \[ \min\left\{Î´^+(H), Î´^-(H) \right\} \ge \frac{d(d+…

math.CO2015

On the size-Ramsey number of hypergraphs

Andrzej Dudek, Steven La Fleur, Dhruv Mubayi +1

The size-Ramsey number of a graph $G$ is the minimum number of edges in a graph $H$ such that every 2-edge-coloring of $H$ yields a monochromatic copy of $G$ . Size-Ramsey numbers o…

math.CO2004

A sharp threshold for random graphs with a monochromatic triangle in every edge coloring

Ehud Friedgut, Vojtech Rodl, Andrzej Rucinski +1

Let $R$ be the set of all finite graphs $G$ with the Ramsey property that every coloring of the edges of $G$ by two colors yields a monochromatic triangle. In this paper we establ…

math.CO2025

The number of cliques in hypergraphs with forbidden subgraphs

Ayush Basu, Vojtech Rodl, Yi Zhao

We study the maximum number of $r$ -vertex cliques in $(r - 1)$ -uniform hypergraphs not containing complete $r$ -partite hypergraphs $K_{r}^{(r - 1)} (a_{1}, \dots, a_{r})$ . By using the hyperg…