The number of different numbers which are smaller than 2x10^8 and are divisible by 3, can be written by means of 0,1and 2 must be _______

I am getting this as -
3digits - 2⋅3=6
4digits - 2⋅3⋅3=18
5 digits - 2⋅3⋅3⋅3=54
6digits - 2⋅3⋅3⋅3⋅3=162
7 digits - 2⋅3⋅3⋅3⋅3⋅3=486
8 digits - 2.3.3.3.3.3.3 = 1458

From 10^8 to 2×10^8- 2⋅3⋅3⋅3⋅3⋅3⋅3⋅3⋅3/2=2187

On adding
4371 
This is the correct answer