Limits RegistryPUBLIC RECORD
Limits RegistryJames D. Allen and, independently, Victor Allis both solved Connect Four in October 1988, proving the first player can always force a win by starting in the center column. Allis's solution used a knowledge-based approach with nine strategic rules; the game was later 'strongly solved' (giving the exact win/loss/draw outcome from every reachable position, not just the starting one) via exhaustive computer search by Allis and, independently, John Tromp.
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James D. Allen and, independently, Victor Allis both solved Connect Four in October 1988, proving the first player can always force a win by starting in the center column. Allis's solution used a knowledge-based approach with nine strategic rules; the game was later 'strongly solved' (giving the exact win/loss/draw outcome from every reachable position, not just the starting one) via exhaustive computer search by Allis and, independently, John Tromp.
On the standard 7-column, 6-row Connect Four board, the first player can always force a win with perfect play.
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Permanent ID limitsregistry.com/limits/LR-CONNECT-FOUR-SOLVED
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Limits Registry. LR-CONNECT-FOUR-SOLVED. Connect Four formally solved (first-player win). 2026.