On an 8 x 8 chessboard, place three white queens, two white knights, and one white rook so that every cell of the board is under attack by at least one piece not standing on it.
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asked Feb 27, 2021 at 15:45
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8$\begingroup$ Oh wow, you've written a puzzle book! Kudos! $\endgroup$– hexominoCommented Feb 27, 2021 at 16:05
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1 Answer
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I used integer linear programming (and, sorry, a computer):
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The solution is unique up to rotation and reflection.
