On May 14 (Wednesday) at 3:00 p.m. in Room 503 of IMI, a meeting of the Seminar of the ORPS Department will be held. A talk on: Busy Beaver for n=5, or How Complex are the Simple Programs will be delivered by Georgi Georgiec, Faculty of Mathematics and Informatics, Sofia University. Abstract. How long can a Turing machine with 5 states and the alphabet {0,1} run before it stops? The tape is initially filled with zeros. Known as “Busy Beaver for n=5” or BB(5), the problem is understandable to any student interested in programming. Solving it took 40 years and demonstrated how complex semantic analysis of even microscopic programs is. The story was told in a fascinating way a year ago in Quanta Magazine: [...]