2020 Cayley Problem 9

Shaded and unshaded squares are arranged in rows so that:

- the first row consists of one unshaded square, - each row begins with an unshaded square, - the squares in each row alternate between unshaded and shaded, and - each row after the first has two more squares than the previous row.

The first 4 rows are shown. The number of shaded squares in the 2020th row is

\textbf{(A)}\ 2022\quad \textbf{(B)}\ 2021\quad \textbf{(C)}\ 2020\quad \textbf{(D)}\ 2019\quad \textbf{(E)}\ 2018

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Cayley contests here.