How much money would you have in 15 days if you get a penny doubled each day?

1. 1cents = 2^0 = 2^(d-1).

2. 2cents = 2^1 = 2^(d-1)
3. 4cents = 2^2 = 2^(d-1).

15. 2^(d-1) = 2^(15-1) = 2^14 = 16,384 Cents(pennies) = $163.84.