*********************************** * Princeton Discrete Math Seminar * *********************************** Speaker: Tung Nguyen (Oxford) Thursday 26th February, 3:00 in Fine Hall 224. Title: Polynomial 𝜒-boundedness for excluding the five-vertex path We overview the recent resolution of a 1985 open problem of Gyárfás, that chromatic number is polynomially bounded by clique number for graphs with no induced five-vertex path. The proof introduces a chromatic density framework involving chromatic quasirandomness and chromatic density increment, which allows us to deduce the desired statement from the Erdős–Hajnal result for the five-vertex path. ---------------------------------- Anyone wishing to be added to or removed from the mailing list should contact Paul Seymour (pds@math.princeton.edu)