All these "Self-referential" number squares have unique solutions. Enjoy! Click on them for larger versions.
Learn how to play on Wikipedia. The fourth clue needs explaining: Take the total number of bridges which come in contact with islands in Column 1 (i.e. B, F and I). Then this divides by 3 is the same as the total for A,C and G divides by 3, and is the same as the total of D and H divides by 2, and is the same as the total number at E. If a bridge connects two islands in the same column it is only counted once. So for instance, if D joined to E and H, and H just joined to D, then the average for column 3 would be 1 (as there are two bridges which come in contact with these islands, divides by 2). ~~~~~~~~Much less fun: More challenging is this Number Theory 'routes' puzzle (click to enlarge): For this you must find a number which satisfies some route, and then show it is the unique number which satisfies some route (i.e. every other route is contradictory and no other number fulfils that route). See the blog entry on it. KenKen |

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