Andrzej Grzegorczyk [ˈandʐɛj ɡʐɛˈɡɔrt͡ʂɨk] (August 22, 1922 – March 20, 2014) was a Polish mathematician. He is known for his work in computability, logic, and the foundations of mathematics (Krajewski and Woleński, 2008).
Grzegorczyk was born in Warsaw, Commonwealth of Poland. he became the first to describe the Grzegorczyk hierarchy, a subrecursive hierarchy that foreshadowed computational complexity theory. He died in Warsaw on March 20, 2014, of natural causes, at the age of 91.
- Stanisław Krajewski and Jan Woleński (2008), "Andrzej Grzegorczyk: Logic and Philosophy", Fundamenta Informaticae, v. 81 n. 1–3, pp. 1–17. ISSN 0169-2968