演讲者:吕本建(北京师范大学)
时间:2020-11-05 16:00-17:00
地点:腾讯会议 ID 379 344 430
Let ℱ be a family of k -subsets of an n-set. The family ℱ is said to be t -intersecting if the size of the intersection of any two subsets in ℱ is not less than t. A t-intersecting family ℱ is said to be trivial if ℱ consists of subsets which contain a fixed t-subset of the n-set. The Erdős-Ko-Rado theorem describes the size and structure of a maximum t-intersecting family, and the Hilton-Milner theorem describes the size and structure of a maximum non-trivial 1-intersecting family. In this talk, we show some results about the structure of maximal non-trivial t-intersecting families with large size for finite sets and vector spaces.