this thing is amazing! i wonder how he does it.

Simple math. Do what it says but don’t click the ball. Do it with several more times with different numbers and you will find that it always comes up with the same symbol.

[Edit] For an easy cheat, look at the zero symbol. That is what the symbol will be. Heh, sorry to spoil the fun…:o

Um, in decimal system if you do this arithmetic trick you always end up with a multiple of 9…and these all have the same symbol.

0, 9, 18, 27, 36, 45, 54, 63, 72, 81

ohhhhhhh… now i get it…

The list is bigger than that:

0, 9, 18, 22, 27, 34, 36, 45, 54, 59, 63, 66, 72, 81