Uploaded December 2025 | Updated September 2026, 2 weeks ago

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Featuring Tom Crawford (happy birthday!) - More links & stuff in full description below ↓↓↓

Extra footage from this video and interview - youtu.be/4rdLQso6_8U

See our original video from 2012 - youtube.com/watch?v=a2ey9a70yY0

Tom Crawford playlist on Numberphile - youtube.com/playlist?list=PLt5AfwLFPxWJ2TNTA79reKQ6S88kTvDR-

Tom Crawford website - tomrocksmaths.com
Tom's YouTube channel - youtube.com/tomrocksmaths

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We are also grateful for support from the Ben Delo Foundation - delo.org

NUMBERPHILE
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Videos by Brady Haran
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