yes, !! is also a math symbol
12:25
What Multiplication was like in the 1500s
12:11
Simple Explanation of the Birthday Paradox
18:48
The Unlikeliness of Numbers Sharing Factors
7:36
I Learned How to Divide by Zero (Don't Tell Your Teacher)
19:37
Pourquoi ce puzzle est impossible
24:00
The Subfactorial is Hilarious
11:31
Solving a 'Harvard' University entrance exam
8:28