摘要
Denote C0(I, I) as the set of all continuous mappings of the interval. Let f∈C0(I, I), for any positive integer n, we define fn inductively byf1= f, fn=f·fn-1 and f0=the identity map.Definition 1. Let p∈I. If. there exists a positive integer n, such that fn(p)=p, then p is called a periodic point of f.