The Unsolved Lollipop Problem - Numberphile

Featuring Neil Sloane - more details below.

Gear Train (episode sponsor) is at https://www.metmo.co.uk/collections/gear-train with discount code NUMBERPHILE10OFF

More Neil Sloane videos at: https://www.youtube.com/playlist?list=PLt5AfwLFPxWJXQqPe_llzWmTHMPb9QvV2

Neil Sloane is the founder of the OEIS: https://oeis.org/

Lollipop Numbers: https://oeis.org/A389624