András Hajnal

András Hajnal ( born May 13, 1931 in Hungary) is a Hungarian mathematician.

Hajnal studied mathematics at the Eotvos Lorand University in Budapest, where in 1953 he received his diploma. It was established in 1957 with László Kalmár PhD (Candidate items) and 1962 Habilitation ( PhD ). From 1956 he taught at the Eötvös Lorand University. 1994 gin g it to the USA. At Rutgers University, where he retired in 2004 He was the Director of The DIMACS ( Center for Discrete Mathematics and Theoretical Computer Science).

Hajnal is concerned with set theory and combinatorics. He worked closely with Paul Erdős with whom he published 56 works. From him and his students Endre Szemerédi the Hajnal - Szemeredi Theorem on graphs derived colorings (1970), originally conjectured by Erdős. It states that for graphs with maximum node degree k as uniform as possible coloring with k 1 colors exist. A set of axiomatic set theory over a partition function is named after him and James Baumgartner.

Hajnal was since 1982 a member of the Hungarian Academy of Sciences and headed the Mathematics Institute in 1982 until 1992. 1980 to 1990 he was secretary of the Janos Bolyai Mathematical Society and its president from 1990 to 1996. In 1974 he was invited speaker at the International Congress of Mathematicians in Vancouver ( Results and independence results in set theoretical topology ). He is a Fellow of the American Mathematical Society.

Hajnal is an avid chess player.

Writings

• With Hamburger: Set Theory, London Mathematical Society Student Texts, Cambridge University Press 1999
• With Paul Erdős, Attila Máté, Richard Rado: Combinatorial set theory: partition relations for cardinals, North -Holland, 1984, Studies in Logic and the Foundations of Mathematics Bd.106.
• Publisher with Béla Bollobás, Alan Baker: A tribute to Paul Erdös, Cambridge University Press 1990