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MTD-f

MTD(f), is a minimax search algorithm, developed in 1994 by Aske Plaat, Jonathan Schaeffer, Wim Pijls, and Arie de Bruin. Experiments with tournament-quality chess, checkers, and Othello programs show it to be the most efficient minimax algorithm. The name MTD(f) is an abbreviation for MTD(n,f) (Memory-enhanced Test Driver with node n and value f). It is an alternative to the alpha-beta pruning algorithm.