Henry Ernest Dudeney may be among the most significant puzzle inventors who ever lived. He was born in Mayfield, England, in 1857, the son of a village schoolteacher, and he died in 1930. Dudeney designed brainteasers for newspapers and magazines regularly for decades, and he later compiled most of his puzzles into books. This head-scratcher comes from his 1917 book Amusements in Mathematics.
A traveling salesman who lives in city A wants to visit all cities from B to P over the course of a week, though not necessarily in alphabetical order, and return to A at the end. He plans to enter each city exactly once. The blue lines are the only roads connecting the 16 cities. The traveling salesman may use only a straight route between any two cities; he is not allowed to turn at the intersection of two streets. How many different routes are possible?
View puzzle with solution at this link.
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Editor’s Note: The version of the puzzle that appeared in the print edition of the July/August 2024 issue incorrectly included connections between C and I and between I and M. The error did not impact the solution.
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