Matt Parker explores caboose numbers, also known as Euler's Lucky Numbers. Part 2 is here: --- More links & stuff in full description below ↓↓↓ Get your signed copy of Love Triangle at Love Triangle on Amazon US (unsigned): And on Amazon UK (unsigned): More Matt on Numberphile: Matt's own channel is Stand-up Maths: Euler's Lucky Numbers on the OEIS: Patreon: Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: We're also supported by the Simons Laufer Mathematical Sciences Institute (formerly MSRI): Our thanks also to the Simons Foundation: NUMBERPHILE Website: Numberphile on Facebook: Numberphile tweets: Subscribe: Videos by Brady Haran Thanks to fact checkers from The Numberphile Society, including Debbie Chakour and CJ Smith. Numberphile T-Shirts and Merch: Brady's videos subreddit: Brady's latest videos across all channels: Sign up for (occasional) emails: