Academy of Mathematics and Systems Science, CAS
Colloquia & Seminars

Speaker:	周进鑫教授,北京交通大学
Inviter:
Title:	Locally bi-2-transitive graphs and cycle-regular graphs
Language:	Chinese
Time & Venue:	2023.05.25 08:20-09:00 N620
Abstract:	In this talk, I shall discuss the characterization of edge-girth-regular and locally bi-2-transitive graphs of girth 3. It is proved that a graph G of girth 3 is edge-girth-regular and locally bi-2-transitive if and only if G is the line graph of a semi-symmetric locally 3-transitive graph. Then as an application, we prove that every tetravalent edge-girth-regular locally bi-2-transitive graph of girth 3 is cycle-regular. This shows that vertex-transitive cycle-regular graphs need not to be edge-transitive, and hence resolves the problem posed by Fouquet and Hahn from 2001.