TOT 245 1990 Spring O J3 27 equal cubes, 9 red, 9 blue , 9 white
Source:
March 12, 2021
combinatoricscombinatorial geometryColoring
Problem Statement
Is it possible to put together equal cubes, red, blue and white, so as to obtain a big cube in which each row (parallel to an arbitrary edge of the cube) contains three cubes with exactly two different colours? (S. Fomin, Leningrad)