(related to Problem: The Five Dogs Puzzle)

The diagrams show four fundamentally different solutions. In the case of $A$ we can reverse the order so that the single dog is in the bottom row and the other four shifted up two squares. Also, we may use the next column to the right and both of the two central horizontal rows. Thus $A$ gives $8$ solutions. Then B may be reversed and placed in either diagonal, giving $4$ solutions. Similarly, $C$ will give $4$ solutions. The line in $D$ being symmetrical, its reversal will not be different, but it may be disposed in $4$ different directions. We thus have in all $20$ different solutions.


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Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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