报告题目：Partitioning digraphs with outdegree at least 4

摘要：Scott asked the question of determining c_d such that if D is a digraph with m arcs and minimum outdegree d\ge 2 then V(D) has a partition V_1, V_2 such that \min\left\{e(V_1,V_2),e(V_2, V_1)\right\}\geq c_dm, where e(V_1,V_2) (respectively, e(V_2,V_1))

is the number of arcs from V_1 to V_2 (respectively, V_2 to V_1). Lee, Loh, and Sudakov showed that c_2=1/6+o(1) and c_3=1/5+o(1), and conjectured that c_d= \frac{d-1}{2(2d-1)}+o(1) for d\ge 4. In this paper, we show c_4=3/14+o(1) and prove some partial results for d\ge 5.

报告人简介：

刘冠吾，2021年毕业于大连理工大学；2018.10 - 2020.10  在佐治亚理工学院访问；在J. Graph Theory等期刊发表学术论文。

报告时间：2021年10月28号下午16：50--17：30

报告地点：腾讯会议708704754