8:41

An Interesting System of Differential Equations

9:46

An Interesting Nonstandard Equation

18:36

complex numbers tells us that the factorial is very special

16:54

An integral with a classic result

11:36

an interesting integral

10:57

An Interesting Algebraic Expression

15:38

I Played Chess Grandmaster Vladimir Fedoseev

27:20

Now, I can retire.