The appeal of the problem lies in the irregular behavior of the successive iterates . One can measure this behavior using the stopping time, the total stopping time, and the expansion factor defined by

if n has a bounded trajectory and if n has a divergent trajectory. For example n = 27 requires 70 iterations to arrive at the value 1 and

Table 1 illustrates the concepts defined so far by giving data on the iterates for selected values of n.