MathDB
squares black and white, assembling a big one

Source: Nordic Mathematical Contest 1992 #4

October 5, 2017
rectanglecombinatoricsColoring

Problem Statement

Peter has many squares of equal side. Some of the squares are black, some are white. Peter wants to assemble a big square, with side equal to nn sides of the small squares, so that the big square has no rectangle formed by the small squares such that all the squares in the vertices of the rectangle are of equal colour. How big a square is Peter able to assemble?