Featuring Ben Sparks... See https://brilliant.org/numberphile for Brilliant and get 20% off their premium service and 30-day trial (episode sponsor)... More links & stuff in full description below ↓↓↓ This is also widely known as The Locker Problem - we liked the light switches better! More Ben Sparks on Numberphile: http://bit.ly/Sparks_Playlist Ben Sparks on the Numberphile Podcast: https://www.youtube.com/watch?v=-tGni9ObJWk Ben's website: https://www.bensparks.co.uk/ Ben's YouTube channel: https://www.youtube.com/channel/UCNS_GTzkj_-qUoNAGaSX5jA Highly Composite Numbers: https://www.youtube.com/watch?v=2JM2oImb9Qg 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 Videos by Brady Haran 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