On the chromatic number of set systems (Q2748418)

From MaRDI portal





scientific article; zbMATH DE number 1659408
Language Label Description Also known as
English
On the chromatic number of set systems
scientific article; zbMATH DE number 1659408

    Statements

    On the chromatic number of set systems (English)
    0 references
    0 references
    0 references
    0 references
    0 references
    10 February 2002
    0 references
    extremal set theory
    0 references
    uniform hypergraphs
    0 references
    property B
    0 references
    An \((r,l)\) system is an \(r\)-uniform hypergraph in which every set of \(l\) vertices lies in at most one edge. The problem is: what is the minimum number of edges in an \((r,l)\)-system that is not \(k\)-colourable. This question in the case of \(l=2\) is due to Paul Erdős and L. Lovász. This paper gives an essentially identical lower and upper bound (up to constants) for this minimum. The proofs are probabilistic.
    0 references

    Identifiers

    0 references
    0 references
    0 references
    0 references
    0 references
    0 references