
Mathematical Research Seminar
Mathematical research seminar is organized by the departments of Mathematics of two members of the University - UP FAMNIT and Andrej Marušič Institute (UP IAM), every Monday from October to June.
You are cordially invited to attend the lectures.
Datum in ura / Date and time: 10.3.25
(15:00-16:00)
Predavalnica / Location: FAMNIT-MP1
Predavatelj / Lecturer: Štefko Miklavič (University of Primorska, and IMFM)
Naslov / Title: On Q-polynomial distance-regular graphs with girth 6
Vsebina / Abstract:
Let Γ denote a Q-polynomial distance-regular graph with diameter D and valency k ≥ 3. By the result of H. Lewis, the girth of Γ is at most 6. In this talk, we give a classification of graphs that attain this upper bound. We show that Γ has girth 6 if and only if it is either isomorphic to the Odd graph on a set of cardinality 2D +1, or to a generalized hexagon of order (1, k -1).