Sebi and the cube

Sebi likes solving Rubik's cube a lot. He spends a lot of time in getting expertize in solving not only the 3 * 3 * 3 cube, but also the cubes of higher dimensions like 4 * 4 * 4, 5 * 5 * 5 and so on. Chefland has a very famous toy shop which sells Rubik's cubes. This shop has interesting rules. Each day it sells cubes of a fixed dimension. Sebi has to buy new cubes daily primarily due to two rea