Some puzzles requiring no knowledge of knot theory, just a careful inspection of the patterns. A glimpse of the classification of knots and a little about prime knots, crossing numbers and knot arithmetic.
This game is known as Pong hau k'i in China and Ou-moul-ko-no in Korea. Find a friend to play or try the interactive version online.
This Chinese game for two players is a simple version of Wei ch'i or Go. Each player has 20 distinctive pieces - try coins, pebbles, shells. You could try marking the board out in wet sand.
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