Minus Cube Minus Cube The Minus Cube () is a 3D mechanical variant of the n-puzzle which was manufactured in the Soviet Union. It consists of a bonded transparent plastic box containing seven small cubes, each glued together from two U-shape parts: one white and one coloured. The length of one side of the interior of the box is slightly more than twice the length of the side of a small cube. There is an empty space the size of one small cube inside the box and the small cubes are moveable inside the box by tilting the box causing a cube
Combination puzzle can be achieved by randomly placing the coloured stickers on the cube, but not all of these can be achieved by manipulating the cube rotations. Similarly, not all the combinations that are mechanically possible from a disassembled cube are possible by manipulation of the puzzle. Since neither unpeeling the stickers nor disassembling the cube is an allowed operation, the possible operations of rotating various faces limit what can be achieved. Although a mechanical realization of the puzzle is usual, it is not actually necessary. It is only necessary that the rules for the operations are defined. The puzzle can be