I need help with this question...I have no idea how to start it.

A country uses as currency coins with values of 1 cent, 2 cents, 5 cents and 10 cents and bills with values of 5 cents, 10 cents, 20 cents and 100 cents. Find a recurrence relation for the number of ways to pay a bill of n cents if the order in which the coins and bills are paid matters.

ie a(17) = 9494