报告题目：Maximal fractional cross-intersecting families
报 告 人：侯新民，中国科学技术大学
报告摘要：Given an irreducible fraction c/d∈[0,1], a pair (A,ℬ) is called a c/d-cross-intersecting pair of 2[n] if A and ℬ are two families of subsets of [n] such that for every pair A ∈Aand B∈ℬ, |A ∩ B|= c/d|B|. Mathew, Ray, and Srivastava [Fractional cross intersecting families, Graphs and Comb., 2019] proved that |A||ℬ|≤ 2n if (A,ℬ) is a c/d-cross-intersecting pair of 2[n] and characterized all the pairs (A,ℬ) with |A||ℬ|= 2n, such a pair also is called a maximal c/d-cross-intersecting pair of 2[n] , when c/d∈{0,1/2, 1}. In this talk, we characterize all the maximal c/d-cross-intersecting pairs (A,ℬ) when 0<c/d<1 and c/d≠1/2. This result answers a question proposed by Mathew, Ray, and Srivastava .
报告人简介：侯新民，中国科学技术大学数学科学学院，副教授，博士生导师。主要研究领域包括结构图论、极值图论、代数图论、图论及其应用等，已发表学术论文60余篇，主持完成国家自然科学基金4项，省部级项目2项。
报告时间：2022年6月29日 15:00-17:00
报告地点：腾讯会议ID：872 852 525
主办单位：伟德国际1946源自英国
