Henry Ernest Dudeney/Puzzles and Curious Problems/254 - The Flanders Wheel/Solution 1

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Puzzles and Curious Problems by Henry Ernest Dudeney: $254$

The Flanders Wheel
Place eight lettered counters on the wheel as shown.
Dudeney-Puzzles-and-Curious-Problems-254.png
Now move them one at a time along the line from circle to circle
until the word $\text {FLANDERS}$ can be correctly read round the rim of the wheel as at present,
only that the $\text F$ is in the upper circle now occupied by the $\text N$.
Of course two counters cannot be in a circle at the same time.
Find the fewest possible moves.


Solution

Move the counters in the following order:

$\texttt {A N D A F L N D A F D N L D R S D L N A F R S E R S L N A L}$

which is $30$ moves in all.


Historical Note

The $30$-move solution was that given by Dudeney.

The $28$-move solution was reported on by Martin Gardner, who set it as a puzzle for his readers to solve.

He notes that it is isomorphic with a sliding-block puzzle of $8$ blocks on a $3 \times 3$ square array.

He then references his Mathematical Games columns in Scientific American for March and June $1965$.


Sources