How do you transform the pyramid of pennies on the left into the one on the right in the fewest number of moves? Most people move four pennies, but on page 23 Martin Gardner will not only show you how to do it in three but will also derive the mathematical formula that allows you to determine the fewest number of moves required to invert penny triangles of all sizes. Not one to stop at the answer to a problem, Gardner always provides the whys and the wherefores behind any solution in his own elegant, entertaining fashion.

The treats in this book range from penny puzzles and card shuffles to a mathematical journey into the art of M.C.Escher and an attempt
to visualize a four-dimensional object.

**"Would that mathematics had been this much fun at school."**** - Los Angeles ***Times*

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