Lecture by Eric Fusy (École Polytechnique Paris): Bijections between families of walks using oriented planar maps

Jan 13, 2020 | 02:15 PM

When counting walks (with a given step-set), an equi-enumeration phenomenom is often observed between a stronger constraint on the domain and a stronger constraint on the position of the endpoint (a classical one-dimensional example is the fact that positive walks of length 2n are in bijection with walks of length 2n ending at 0, both being counted by the central binomial coefficient). I will show examples of such relations for 2d walks where the equi-enumeration can be bijectively explained using planar maps endowed with certain orientations (Schnyder woods, bipolar orientations).

Time & Location

Jan 13, 2020 | 02:15 PM

Technische Universität Berlin
Institut für Mathematik
Straße des 17. Juni 136
10623 Berlin
Room MA 041 (Ground Floor)

Freie Universität Berlin
Technische Universität Berlin
Humboldt-Universität zu Berlin
Deutsche Forschungsgemeinschaft (DFG)