**Date & Time:** Wednesday, February 13, 2013, 15:30-17:30.

**Venue:** Ramanujan Hall

**Title:**The art of irrationality proving

**Speaker:** Prof. Frits Beukers

**Abstract:** Although there are some methods to prove irrationality for large classes of numbers, in many interesting cases the proof is either very ad hoc or no proof is known. In this lecture we discuss a few instances, both old and new.