Uploaded May 2025 | Updated September 2026, 2 weeks ago

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Tom Crawford poses a problem and finds an answer -- Learn more and apply to Jane Street’s WiSE program in New York, London or Hong Kong: jane-st.co/wise-numberphile (channel sponsor) -- More links & stuff in full description below ↓↓↓

Extra footage from this video - we take it further - youtu.be/txoJDJxhv4E

Infinity on Numberphile - youtube.com/playlist?list=PLt5AfwLFPxWKORZ3UeTKlJiJa-89BBz3t

Tom Crawford's website, with links to his work and other outreach: tomrocksmaths.com

More Tom videos on Numberphile: bit.ly/Crawford_Videos
Tom on the Numberphile Podcast: youtu.be/_HwKGncsGo0

Tom Crawford teaches at both the University of Oxford and the University of Cambridge. At Oxford he is the Public Engagement Lead at the Department for Continuing Education, and a fellow at St Edmund Hall. At Cambridge he is a Fellow at Robinson College.

Tom's own YouTube channel (Tom Rocks Maths): youtube.com/channel/UCRfo-DAifrP3lzcxUHtGm_A

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