Roger Apéry

Roger Apéry (14 November 1916 – 18 December 1994) was a Greek-French mathematician most remembered for Apéry's theorem, which states that ζ(3) is an irrational number. Here, ζ denotes the Riemann zeta function.

Apéry was born in Rouen in 1916 to a French mother and Greek father. After studies at the École Normale Supérieure (interrupted by a year as prisoner of war during World War II) he was appointed Lecturer at Rennes. In 1949 he was appointed Professor at the University of Caen where he remained until his retirement. In 1979 he published an unexpected proof of the irrationality of ζ(3), which is the sum of the inverses of the cubes of the positive integers. An indication of the difficulty is that the corresponding problem for other odd powers remains unsolved. Nevertheless, many mathematicians have since worked on the so-called Apéry sequences to seek alternative proofs that might apply to other odd powers (F. Beukers, A. van der Poorten, M. Prevost, K. Ball, T. Rivoal, Wadim Zudilin and others).