Let n represent unknown number
4n^2 is the final answer. Hope it help!
The function appears to be L(legos) = T(tower)^3
L = T^3
This checks out for t =1,2,3,4
The 100th tower would have 100^3 legos.
100^3 = 1,000,000.
The 100th tower would have 1 million cubes