已知数列{an},求an的最大值或最小值,这是在解决数列问题时常常遇到的问题,其流行解法是:要使an最大,则应满足an≥an-1,an≥an+1,其中n≥2.同样,要使an最小,则应满足an≤an-1,an≤an+1,其中n≥2.在文[1]中,作者通过举例,发现在有些问题中,由这种流行解法得到的结果并不是最大的 Known series {an}, find the maximum or minimum an, which is often encountered in the solution to the problem of a series of problems, the popular solution is: to make an maximum, it should meet an ≥ an-1, an ≥ an + 1, where n ≥ 2. Similarly, to make an minimum, then an≤an-1, an≤an + 1, where n≥2. In [1], the author by example, found that in some In the problem, the result obtained by this popular solution is not the greatest