Double Counting by Archit Manas
1:27:34
Quadratic Reciprocity by Rushil Mathur
1:36:37
Inversion by Raghav Jeyan
26:12
How to Remember Everything You Read
15:32
A beautiful example of double counting
21:40
Same perimeter, different areas: Which is the largest? The Isoperimetric Problem
12:16
7 Outside The Box Puzzles
2:20:10
Combinatorial Thinking and Crafting Solutions by Om Kutte
17:05