MathDB
smallest no of 3-cell corners in a 6x6 square grid so that

Source: Caucasus 2015 7.5

April 26, 2019
combinatoricscombinatorial geometrysquare grid

Problem Statement

What is the smallest number of 33-cell corners needed to be painted in a 6×66\times 6 square so that it was impossible to paint more than one corner of it? (The painted corners should not overlap.)