Who discovered this mysteriously accurate value for π ? Celebrate #PiDay with the untold story of 355/113 and learn a history of pi that schools do not teach.
0:00 intro
2:25 accurate 355/113
4:05 the mystery
6:42 summary facts
7:52 Liu Hui
14:40 Zu Chongzhi
15:58 He Chengtian
22:07 deriving 355/113
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https://commons.wikimedia.org/wiki/File:Liu_hui.jpg
https://commons.wikimedia.org/wiki/File:%E7%A5%96%E5%86%B2%E4%B9%8B%E9%93%9C%E5%83%8F.jpg
Story of pi
https://www.youtube.com/watch?v=tB0zjT75yto
https://en.wikipedia.org/wiki/Rod_calculus
Milü
https://en.wikipedia.org/wiki/Mil%C3%BC
Chronology of computation of π
https://en.wikipedia.org/wiki/Chronology_of_computation_of_%CF%80
Liu Hui's π algorithm
https://en.wikipedia.org/wiki/Liu_Hui%27s_%CF%80_algorithm
Pi
https://en.wikipedia.org/wiki/Pi
Mystery of 355 over 113
https://web.archive.org/web/20100322225540/https://davidbau.com/archives/2010/03/14/the_mystery_of_355113.html
https://news.ycombinator.com/item?id=4285531
https://en.wikipedia.org/wiki/Zu_Chongzhi
mediant
https://en.wikipedia.org/wiki/Mediant_(mathematics)
https://math.stackexchange.com/questions/1989104/mediant-inequality-proof-fracab-fracacbd-fraccd
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