Weighted

The proportions of child values to each other are maintained when the value of their parent is increased or decreased.

Weighted allocation: #W[value]:

If you use weighted allocation to write a value to a parent cell that is, for example, double the existing value, the value of each child also doubles.

Weighted alteration: &W[value]:

If you use weighted alteration to write a value to a parent cell that is, for example, double the existing value, the value of each child is doubled and added to the existing value.

Example:

The value of the parent cell is 9 and the value of each of its three children is 3. You write 18 to the parent cell with weighted alteration. The value of each child cell is doubled and added to the existing value. So, the value of each child cell becomes 9. The value of the parent cell becomes 27.