One way to avoid the overhead of multiple calls which evaluate the same value of the function in Exercise 9.9 is to avoid recursive calls altogether. One way to do this is to calculate the values in a...

One way to avoid the overhead of multiple calls which evaluate the same value of the function in Exercise 9.9 is to avoid recursive calls altogether. One way to do this is to calculate the values in a ‘bottom up’ way, starting with the values for the lowest values of n and ‘building up’. This way, we can visit each value of n once only