MathDB
Connected intersections of k subsets

Source:

January 22, 2011
floor functionceiling functioncombinatorics proposedcombinatorics

Problem Statement

Let nn be a positive integer and A={1,2,,n}A=\{ 1,2,\ldots ,n\}. A subset of AA is said to be connected if it consists of one element or several consecutive elements. Determine the maximum kk for which there exist kk distinct subsets of AA such that the intersection of any two of them is connected.