Uploaded October 2023 | Updated September 2026, 2 weeks ago

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Featuring Sophie Maclean and superfactorials. Try the Halfsies challenge at brilliant.org/challenge/numberphile (and tell us your score!) or go to Brilliant's courses and start for free at brilliant.org/numberphile (episode sponsor)
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Sophie Maclean is based at Kings College, London: sophiethemathmo.wordpress.com

More Sophie on Numberphile: bit.ly/Sophie_Numberphile

Superpermutations: youtu.be/wJGE4aEWc28
Superhero Triangles: youtu.be/UIjeCKPHbso
The Super Bottle: youtu.be/8dHMpnfFdtc

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