Select a separating family
Source: Miklós Schweitzer 2014, problem 1
December 23, 2014
ceiling functionlogarithmscombinatorics unsolvedcombinatorics
Problem Statement
Let be a positive integer. Let be a family of sets that contains more than half of all subsets of an -element set . Prove that from we can select sets that form a separating family on , i.e., for any two distinct elements of there is a selected set containing exactly one of the two elements.Moderator says: http://www.artofproblemsolving.com/Forum/viewtopic.php?f=41&t=614827&hilit=Schweitzer+2014+separating