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Nimatron and friend
A game, of which there are many different versions, that involves two players alternately removing at least one item from one of two or more piles or rows. The person who picks up the last item wins. In one form of the game, five rows of matches are laid out in such a way that there is one match in the first row, two matches in the second, and so on, down to five matches in the bottom row. Players take turns to remove any non-zero number of matches from any one row. The game may have originated in China. The name "Nim" was coined Charles Bouton, an associate professor of mathematics at Harvard at the turn of the 20th century, who took it from an archaic English word meaning to steal or to take away. In 1901 he published a full analysis of Nim and proof of a winning strategy.1

The first Nim-playing computer, the Nimatron, a one-ton behemoth, was built in 1940 by the Westinghouse Electrical Corporation and was exhibited at the New York Worlds Fair. It played 100,000 games against spectators and attendants, and won an impressive 90% of the time; most of its loses came at the hands of attendants who were instructed to reassure incredulous onlookers that the machine could be beaten! In 1951 a Nim-playing robot, the Nimrod, was shown at the Festival of Britain, and later at the Berlin trade fair. It was so popular that spectators entirely ignored a bar at the other end of the room where free drinks were being offered. Eventually the local police had to be called in to control the crowds.


  1. Bouton, Charles L. "Nim, a Game with a Complete Mathematical Theory." Annals of Mathematics, Series 2. 3: 35-39, (1901-1902).
  2. Gardner, M. Mathematical Puzzles and Diversions. New York: Simon and Schuster, 1959.

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