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Do you need to use any of the 26 cards that you turned up at the start of the trick?
Is this always the case?
Imagine you have six different colours of paint. You paint a cube using a different colour for each of the six faces. How many different cubes can be painted using the same set of six colours?
Given a 2 by 2 by 2 skeletal cube with one route `down' the cube. How many routes are there from A to B?