András Hajnal (May 13, 1931 – July 30, 2016[1][2]) was a professor of mathematics at Rutgers University[3] and a member of the Hungarian Academy of Sciences[4] known for his work in set theory and combinatorics.
[5] He became a member of the Hungarian Academy of Sciences in 1982, and directed its mathematical institute from 1982 to 1992.
Hajnal was also one of the honorary presidents of the European Set Theory Society.
[9] Among the many co-authors of Paul Erdős, he had the second largest number of joint papers, 56.
[10] With Peter Hamburger, he wrote a textbook, Set Theory (Cambridge University Press, 1999, ISBN 0-521-59667-X).