报告题目: Maximum Even Factors of Graphs
报告人：范更华 福州大学
报告时间：12月2日（周三）16:00-17:00
报告地点：1611
摘要：
A spanning subgraph F of a graph G is called an even factor of G if each vertex of F has even degree at least 2 in F.
We prove that if a graph G has an even factor, then it has an even factor F with |E(F)| ≥4/7 (|E
(G| + 1), which is best possible. Furthermore, we characterize all the extremal graphs, showing that if |E(H)| ≤4/7
(|E(G)| + 1) for every even factor H of G, then G belongs to a specified class of graphs.