MathDB
colouring squares

Source: tuymaada 2006 - problem 7

July 17, 2006
geometryrectanglegeometric transformationrotationinductionvectorabsolute value

Problem Statement

From a n×(n1)n\times (n-1) rectangle divided into unit squares, we cut the corner, which consists of the first row and the first column. (that is, the corner has 2n22n-2 unit squares). For the following, when we say corner we reffer to the above definition, along with rotations and symmetry. Consider an infinite lattice of unit squares. We will color the squares with kk colors, such that for any corner, the squares in that corner are coloured differently (that means that there are no squares coloured with the same colour). Find out the minimum of kk.
Proposed by S. Berlov