Mesolabe Compass and Square Roots - Numberphile
6:50
Russian Multiplication - Numberphile
13:25
Impossible Squares - Numberphile
10:55
Square roots explained Bob Ross style
15:06
Johnny Ball and Measuring the Earth
16:11
O Quadrado Anti-Parker - Numberphile
13:48
Dungeon Numbers - Numberphile
17:05
Stones on an Infinite Chessboard - Numberphile
17:12