Shoutbox

Hmmm, if you substract the second number, you basicly round down to the lowest ten,
after that you substract one more, so basicly this are the only values you can get:
10 -> 9
20 -> 18
30 -> 27
40 -> 36
50 -> 45
60 -> 54
70 -> 63
80 -> 72
90 -> 81
(all multiples of 9 )
If you look closely, you will see that those numbers always have the same symbol, the other numbers that can not be obtained are simply there to distract you,
the program picks a symbol, puts it in all the predefined numbers, and fills the rest with bullshit. once you click the magic square, it displays the symbol it chose

more proof: