Tri-connected squares
Source: APMO 2018 P3
June 24, 2018
combinatoricsAPMO
Problem Statement
A collection of squares on the plane is called tri-connected if the following criteria are satisfied:(i) All the squares are congruent.
(ii) If two squares have a point in common, then is a vertex of each of the squares.
(iii) Each square touches exactly three other squares.How many positive integers are there with , such that there exists a collection of squares that is tri-connected?