已知等比数列{a
n}的前n项和为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428021_ST/0.png)
,正数数列{b
n}的首项为c,且满足:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428021_ST/1.png)
.记数列{b
nb
n+1}前n项和为T
n.
(Ⅰ)求c的值;
(Ⅱ)求数列{b
n}的通项公式;
(Ⅲ)是否存在正整数m,n,且1<m<n,使得T
1,T
m,T
n成等比数列?若存在,求出m,n的值,若不存在,说明理由.
考点分析:
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