 Gabriel Sudan

Gabriel Sudan (April 14, 1899 – June 22, 1977) was a Romanian mathematician, known for the Sudan function (1927), an important example in the theory of computation, similar to the Ackermann function (1928).Gabriel Sudan received his Ph.D. from the University of Göttingen in 1925 for his thesis "Über die geordneten Mengen" ("On the theory of ordered sets"), supervised by David Hilbert.