Gyula O.H. Katona

Gyula O. H. Katona is a Hungarian mathematician known for his work in combinatorial set theory, and especially for the Kruskal–Katona theorem and his beautiful and elegant proof of the Erdős–Ko–Rado theorem in which he discovered a new method, now called Katona's cycle method. Since then, this method has become a powerful tool in proving many interesting results in extremal set theory. He is affiliated with the Alfréd Rényi Institute of Mathematics of the Hungarian Academy of Sciences.