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arXiv · 1412.7749

Concerning the bookshelf problem

Lev Radzivilovsky·Grigori Yurgin
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Abstract

We discuss the following folklore problem. On a bookshelf, there are $N$ tomes of the Encyclopedia in random order. Each hour, a librarian takes a tome which stands not on its place, and puts it in its place. Show that the process will stop. A natural additional question is how many moves are required for the process to stop. We show that the process can last $2^{N-1}-1$ moves, and that it will stop anyway in less than $2^N$ moves.

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Lev Radzivilovsky, Grigori Yurgin. 2014-12-24. Concerning the bookshelf problem. https://arxiv.org/abs/1412.7749

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