Medfarm Play

Counting objects up to symmetry is a classical subject in combinatorics. In this talk, we take a probabilistic viewpoint and study the automorphism group of two types of random trees: Galton-Watson trees (a family of random rooted trees that include, for example, plane, binary and labelled trees) as well as Pólya trees (rooted, unordered and unlabelled trees). Specifically, we prove that, in both cases, the size of the automorphism group follows a log-normal distribution, asymptotically as the size of the tree goes to infinity. Our proofs use both probabilistic tools and methods from analytic combinatorics.

Kontaktperson för denna film
Paul Thévenin, Sannolikhetsteori och kombinatorik

Kanalinformation

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