There is one blue cube and many white ones - all of equal size. Try to arrange the white cubes around the blue one so that they touch it. Overlapping is not allowed. Valid touching is considered touching particular area on the surface of the cube. Touching in one single point or line (respectively vertex or edge) is not allowed. What is the maximum number of white cubes that can be arranged that way?

Many years ago Martin Gardner presented two solutions with 22 cubes. He also mentioned that there are solutions with 23 and even 24 cubes, but they are too complicated to display.



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