报 告 人：周进鑫 教授

报告题目：On primitive 2-closed permutation groups of rank at most four 

报告时间：2024年11月15日（周五）下午4：00

报告地点：静远楼1508会议室

主办单位：数学与统计学院、数学研究院、科学技术研究院

报告人简介：

       周进鑫，北京交通大学数学与统计学院教授，博导，国家自然科学基金杰出青年基金获得者。主要从事对称图论研究。在组合数学、图论、代数等领域权威期刊Journal of Combinatorial Theory, Series A/B, Combinatorica, European Journal of Combiatorics, Journal of Graph Theory, Journal of Algebra, Journal of Algebraic Combintorics等上发表论文100余篇。主持和参与国家自然科学基金等科研项目10余项。

报告摘要：

       In this talk, I will discuss the characterisation of the primitive 2-closed groups $G$ of rank at most four that are not the automorphism group of a graph or digraph, and we show that if the degree is at least 2402 then there are just two infinite families or $G\leq {\rm A\Gamma L}_1(p^d)$, the 1-dimensional affine semilinear group. To the best of our knowledge, these are the first known examples of non-regular 2-closed groups that are not the automorphism group of a graph or digraph. This is a joint work with Michael Giudici and Luke Morgan.