I found this puzzle to be misleading. It says that when you choose a book, you must "take" the adjacent two books. Meaning those books are no longer there. If you take the instructions literally, you can only choose a maximum of two books before there are no longer any books with two adjacent books in each direction. If you allow gaps in what is considered "adjacent," then this can increase to four. It's only 18 if you allow books to be replaced after each choice. But if you can replace after each choice, though, why can't you just move books around at will? Then the answer would be 70. 21:30, November 1, 2012 (UTC)

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