在数列{a
n}中,a
1=1,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101601952226609/SYS201311031016019522266020_ST/0.png)
,其中n∈N
*.
(1)求证:数列{b
n}是等差数列;
(2)求证:在数列{a
n}中对于任意的n∈N
*,都有a
n+1<a
n;
(3)设
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101601952226609/SYS201311031016019522266020_ST/1.png)
,试问数列{c
n}中是否存在三项,它们可以构成等差数列?如果存在,求出这三项;如果不存在,说明理由.
考点分析:
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