Hunt for the Elusive 4th Klein Bottle - Numberphile
16:41
Super Bottle - Numberphile
26:19
Perfect Shapes in Higher Dimensions - Numberphile
26:36
Epic Circles - Numberphile
16:10
The Puzzling Fourth Dimension (and exotic shapes) - Numberphile
11:44
The 17-Klein Bottle - Numberphile
14:42
The Seven Bridges of Königsberg - Numberphile
23:38
More on Bertrand's Paradox (with 3blue1brown) - Numberphile
12:58