Article isn't loading for me, but each (3+) tile can be represented as 3 * 2^k, and it's score is calculated as 3^(k+1)

    3   -> 3 * 2^0 -> 3^1 -> 3 pts
    6   -> 3 * 2^1 -> 3^2 -> 9 pts
    192 -> 3 * 2^6 -> 3^7 -> 2,187 pts

I may have an off-by-one (degree) error though. It helps to be a big math geek who looks for exponents everywhere.