This puzzle involves three pegs and any number of rings, each of a different size. To begin with the rings are stacked in sequence, largest on the bottom, on peg A. The aim of the puzzle is to move the rings from peg A to peg C using peg B with the single rule that a larger ring should never be placed over a smaller one.
Start with two rings and work out a method that will move them across the pegs in the required way. What is the minimum number of moves? Now try three rings and finally four. Is there a formula that expresses the number of moves that a given number of rings will require? Can you see a pattern in the moves?