How much money must you deposit into a savings account at the end of each year at 4% interest compounded annually in order to earn $9,778.08 interest during a 20-year period?

I got Future value = 8209.13 + 9778.08 = $17987.21

But the formula to insert is {[(1 + i)^n - 1]/i}.

I keep missing the mark but not sure what I am doing wrong