Answer:
505
Explanation:
you first do 2020x2020 because you can see from the pattern, the inside squares are 1x1, 2x2, 3x3, so the 2020th inside squares would be 2020x2020. then, you would do 2020x4 for the shaded squares because if you see from the pattern, its 1x4, 2x4, 3x4, so the 2020th would be 2020x4. then you divide
which is 505.