Problem 4. Use generating functions to find the generating function and closed form formula for a bank balance, where the interest rate is 2 percent per year, the initial deposit is $2,000, and an additional $300 is deposited at the start of each year (as in Example 8.2). Problem 4. Use generating functions to find the generating function and closed form formula for a bank balance, where the interest rate is 2 percent per year, the initial deposit is $2,000, and an additional $300 is deposited at the start of each year (as in Example 8.2)