The exponentiation is the action of multiplying a number by itself a given number of times.

For instance, 3 to the power 2 is 3x3=9, 10 to the power 3 is 10x10x10=1,000.

A sequence starting wit u(0)=C and continuing with the iterative formula u(n+1)=a x u(n) has for value u(n) equal to C multiplied by **a** to the power n.

Such a sequence is called a geometrical sequence of initial point C and "reason" a>0.

There are 3 cases for the behavior of the sequence:

- if a>1, the sequence goes to...