MathDB
squares intersection in the plane

Source: Russia 1995

March 8, 2005
inductioncombinatorics proposedcombinatorics

Problem Statement

there are some identical squares with sides parallel, in a plane. Among any k+1k+1 of them, there are two with a point in common. Prove they can be divided into 2kāˆ’12k-1 sets, such that all the squares in one set aint pairwise disjoint.