Lewis Carroll's Pillow Problem - Numberphile
17:12
A Problem with Rectangles - Numberphile
18:36
Game of Cat and Mouse - Numberphile
19:01
A New Discovery about Dodecahedrons - Numberphile
17:45
The Riddle That Seems Impossible Even If You Know The Answer
14:51
The Brick Factory Problem - Numberphile
28:28
Russell's Paradox - a simple explanation of a profound problem
15:27
Euler Squares - Numberphile
23:44