Algorithm

Based on the consideration in the previous section, we obtain the following algorithm.

1. Find by (17) or (19).
2. The initial values and are immediately determined by using (11) and (12).
3. Calculate rhs of (21), then get and by (22).  
4. Find and in time by (23) or (25) recursively for each i.  
5. Repeat 3-4 until i=n.
6. Obtain n-digit number by (5).