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- A row of 2015 red and white chips 5 answers
1000 white stones and 1 black stone are arranged in a row. A move consists in selecting one black stone and changing the color of the 2 neighbouring stones (or changing the color of 1 neighboring stone if the selected stone is at the end of the row).
Find all possible initial positions of the black stone, so that all stones can be made black by moves.