Featuring Neil Sloane. See https://brilliant.org/numberphile for Brilliant and get 20% off their premium service (episode sponsor) More links & stuff in full description below ↓↓↓ Correction at 4:08… Neil says “then we get twice 61" instead of “about twice 61". The actual result is 120, not 122 as labelled. Neil Sloane is founder of the legendary OEIS: https://oeis.org/ Yellowstone Permutation and its wonderful geysers: https://oeis.org/A098550 More Neil Sloane videos: http://bit.ly/Sloane_Numberphile Brady in Iceland: https://www.bradyharanblog.com/iceland-index Numberphile is supported by the Simons Laufer Mathematical Sciences Institute (formerly MSRI): http://bit.ly/MSRINumberphile We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science. https://www.simonsfoundation.org/outreach/science-sandbox/ And support from The Akamai Foundation - dedicated to encouraging the next generation of technology innovators and equitable access to STEM education - https://www.akamai.com/company/corporate-responsibility/akamai-foundation NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook: http://www.facebook.com/numberphile Numberphile tweets: https://twitter.com/numberphile Subscribe: http://bit.ly/Numberphile_Sub Video by Brady Haran and Pete McPartlan Thanks to the Numberphile Society for fact checking, especially Paul Patreon: http://www.patreon.com/numberphile Numberphile T-Shirts and Merch: null Brady's videos subreddit: http://www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: http://www.bradyharanblog.com/ Sign up for (occasional) emails: http://eepurl.com/YdjL9 Shout out to these Patreon supporters: Ben Delo Jeff Straathof Ken Baron Yana Chernobilsky Juan Benet Andy B James Bissonette Jubal John Jeremy Buchanan Steve Crutchfield Ben White Andrei M Burke Tracy Parry Ian George Walker RAD Donato Arnas Bernd Sing Valentin Matthew Schuster Nat Tyce Alfred Wallace Ron Hochsprung Ubiquity Ventures John Zelinka Gnare Alex Khein Michael Dunworth Mirik Gogri Kannan Stanz Heather Liu Doug Hoffman Xavier F. G. John Loach