MathDB
Combinatorics with subsets,SMO 2016P5

Source: Serbia Math Olympiad 2016 Day 2 P5

April 2, 2016
combinatoricsProbabilistic Method

Problem Statement

There are 2n−12n-1 twoelement subsets of set 1,2,...,n1,2,...,n. Prove that one can choose nn out of these such that their union contains no more than 23n+1\frac{2}{3}n+1 elements.
Back to ProblemsView on AoPS