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20232026
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7 papers · 1 filter

math.CO2026

On Ramsey number of Steiner systems

Ayush Basu, Daniel Dobak, Vojtěch Rödl +1

A -uniform hypergraph is called a partial -system if every set of vertices of is contained in at most one edge of . We prove the existence of a pa…

math.CO2025

Relative Turán densities of ordered graphs

Christian Reiher, Vojtěch Rödl, Marcelo Sales +1

We introduce a modification of the Turán density of ordered graphs and investigate this graph parameter.

math.CO2024

Coloring triangles in graphs

Ayush Basu, Vojtěch Rödl, Marcelo Sales

We study quantitative aspects of the following fact: For every graph , there exists a graph with the property that any -coloring of the triangles of yields an induced…

math.CO2024

The -representation number of the random graph

Ayush Basu, Vojtěch Rödl, Marcelo Sales

The -representation number of a graph is the minimum cardinality of the system of vertex subsets with the property that every edge of is covered at least times while…

math.CO2024

Nowhere dense Ramsey sets

Vojtěch Rödl, Marcelo Sales

A set of points in Euclidean space is called \textit{Ramsey} if any finite partition of yields a monochromatic copy of . While character…

math.CO2024

Note on set representation of bounded degree hypergaphs

Ayush Basu, Griffin Johnston, Vojtěch Rödl +1

In their classical paper, Erdős, Goodman and Pósa studied the representation of a graph with vertex set by a family of subsets with the property that $\{i,j\…

math.CO2023

Colouring versus density in integers and Hales-Jewett cubes

Christian Reiher, Vojtěch Rödl, Marcelo Sales

We construct for every integer and every real a set of integers which, when coloured with finitely many colours, contains a monochrom…