Abstract:
Extremal problems concerned with hypergraph colouring first arose in connection with classical investigations in the 1920-30s which gave rise to Ramsey theory. Since then, this area has assumed a central position in extremal combinatorics. This survey is devoted to one well-known problem of hypergraph colouring, the Erdős–Hajnal problem, initially posed in 1961. It opened a line of research in hypergraph theory whose methods and results are widely used in various domains of discrete mathematics.
Bibliography: 109 titles.
Keywords:hypergraph, hypergraph colourings, chromatic numbers, extremal set theory.