A loan of $100,000 is to be repaid with annual payments made at the end of each year. The annual effective rate of interest is 5.5%. The first payment is $1000 and the second is $2000, the third is $3000 and so on. Each successive payment is increased by $1000. The payments continue until the loan is paid(the last payment may not fit into the problem). Find the balance on the loan after the 15th payment.