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Mathematics & Algorithms · Recorded milestone

Computer-assisted proof

Recorded year1976

Appel and Haken prove the four-colour theorem with computer checking.

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Built on

Integrated circuitRecorded · 1958requires
IBM System/360Recorded · 1964enables

Led to

Lean proof assistantRecorded · 2013enables
Machine-native mathematicsRecorded · 2016enables

Sources & evidence

Additional source

Dataset updated 2026-10-18. This individual record has not been separately re-reviewed.