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UKMT Mathematical Olympiad for Girls, 2013

Combinatorics Difficulty 3.0 AMC 10/12 Prove it United Kingdom

A ladybird can move one square up, one square to the right, or one square diagonally down and left, as shown in the diagram, and cannot leave the board. Is it possible for the ladybird to start in the bottom left corner of an $8 \times 8$ board, visit every square exactly once, and return to the bottom left corner?

Figure for this problem

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