512 : Combination

To get a larger number and colorful square by combining squares.

Two squares of the same color and number can be combined in the same row or same column. After combination, the color is constant and the number is added.
A square and two squares around it can be combined, when they are different colors and same number. After combination, the color becomes colorful, the number unchanged.

The target is to get the Colorful 512! And try to get a higher score.