由数列的递推公式求通项公式,往往是通过变形转化为等差或等比数列来解决.变形是关键,有着较强的技巧.这里介绍一种利用不动点来求通项的方法,对解决以下几种类型的题目简单、易行.对于函数f(x),若存在x0,使f(x0)=x0,则称x0为f(x)的不动点.1.形如an+1=pan+q(p≠0).例1已知数列{ The formula for solving a general term by a series of recursive formulae is often solved by transforming it into an arithmetic or mathematical array. Deformation is the key and has strong skills. Here is a method for finding general terms using fixed points. It is simple and easy to solve the following types of questions. For the function f(x), if x0 exists and f(x0) = x0, then x0 is the fixed point of f(x). An+1=pan+q(p≠0). Example 1 Known sequence {