collaborators

8 papers

math.CO2026

Multicolor Ramsey numbers of odd cycles are superexponential

Raphael Steiner

In a recent breakthrough, OpenAI proved that the -color Ramsey number of the triangle grows super-exponentially, more precisely, they proved that $R_k(C_3)\ge k^{k/3-o(k)}…

math.CO2026

The Erdős-Hajnal conjecture for odd-girth

Raphael Steiner

A famous conjecture of Erdős and Hajnal from 1969 states that for every integer there exists a (smallest) function such that every…

math.CO2026

A constant-factor step towards Vizing's conjecture

Raphael Steiner

Vizing's conjecture from 1963, considered by many the most important open problem in the field of graph domination, states that all graphs and satisfy $$γ(G\square H)\ge ΅

math.CO2026

Openly disjoint cycles and directed tree-width of regular digraphs

Raphael Steiner

Given a digraph , let denote the largest integer such that there are openly disjoint cycles through a vertex, i.e., a collection of directed cycles $C_1,\ldots,C_…

math.CO2026

A note on Ramsey numbers for minors

Maria Axenovich, Raphael Steiner

Let be the smallest integer such that any edge coloring of a complete graph on vertices in colors results in a monochromatic -minor, in other wor…

math.CO2026

Coloring small locally sparse degenerate graphs and related problems

Domagoj Bradač, Jacob Fox, Raphael Steiner +2

The classic upper bound on the chromatic number of -degenerate graphs is , shown to be tight by complete graphs. A natural question is whether this bound remains tight if o…