MathDB
k-element subsets with strict relation

Source: Kürschák 2016, problem 1

October 7, 2016
combinatoricsSubsets

Problem Statement

Let 1kn1\le k\le n be integers. At most how many kk-element subsets can we select from {1,2,,n}\{1,2,\dots,n\} such that for any two selected subsets, one of the subsets consists of the kk smallest elements of their union?