Colloquium abstracts

W. Casselman
University of British Columbia, Canada
February 7, 2013

Cornelius Lanczos' mysterious formula for the Gamma function:  In 1964, Cornelius Lanczos proposed entirely without proof a new kind of asymptotic expansion of the Gamma function, very different from Stirling's formula and much more mysterious. In his 2004 UBC thesis a former student of mine, Glen Pugh, derived Lanczos' formula and uncovered some of the most peculiar phenomena I have ever seen in the behaviour of asymptotic expansions. I am not aware that anyone has explained rigourously what is going on.