A Puzzle and a Solution

Let’s say we have a number N of children placed in a circle and playing the following simple game: proceeding around the circle they kick out every Pth of them (of course, P < N).

Of course, what we will obtain is a permutation of the first N natural numbers. The puzzle asks for the order of this permutation (that is the number of times it must be applied to itself to get back to an ordered list.

Read the rest of this entry »