determine maximum real k
Source: Tuymaada 2007, Problem 4
July 15, 2007
combinatorics proposedcombinatorics
Problem Statement
Determine maximum real such that there exist a set and its subsets , , , satisfying the following conditions:
(1) for every two elements of there is an index such that contains neither of these elements;
(2) if any non-negative numbers are assigned to the subsets and then there is an element such that the sum of corresponding to all the subsets that contain is at least .