The following problem was answered by a theorem of Kruskal, Katona, and Lindström about 20 years ago: Given a family of k-element sets ℱ, |ℱ|=m, at least how many (k-d)-element subsets are contained in the members of ℱ? This paper deals with the extremal families, e.g., they are completely described for infinitely many values of m.
- AMS subject classification (1980): 05C35
ASJC Scopus subject areas
- Discrete Mathematics and Combinatorics
- Computational Mathematics