解:(Ⅰ)已知式即
![](http://thumb.1010pic.com/pic5/latex/78440.png)
,故
![](http://thumb.1010pic.com/pic5/latex/78441.png)
.
因为a
n≠0,当然a
n+1≠0,所以a
n+2-a
n=2(n∈N
*).
由于
![](http://thumb.1010pic.com/pic5/latex/78442.png)
,且a
1=1,故a
2=2.
于是a
2m-1=1+2(m-1)=2m-1,a
2m=2+2(m-1)=2m,
所以a
n=n(n∈N
*).
(Ⅱ)由
![](http://thumb.1010pic.com/pic5/latex/78438.png)
,得
![](http://thumb.1010pic.com/pic5/latex/83633.png)
,
![](http://thumb.1010pic.com/pic5/latex/83634.png)
,
故
![](http://thumb.1010pic.com/pic5/latex/78446.png)
.
从而
![](http://thumb.1010pic.com/pic5/latex/83635.png)
.
![](http://thumb.1010pic.com/pic5/latex/83636.png)
=
![](http://thumb.1010pic.com/pic5/latex/83637.png)
因此2T
n-log
2(2a
n+1)=
![](http://thumb.1010pic.com/pic5/latex/83637.png)
-log
2(2n+1)
=
![](http://thumb.1010pic.com/pic5/latex/83638.png)
=
![](http://thumb.1010pic.com/pic5/latex/83639.png)
.
设
![](http://thumb.1010pic.com/pic5/latex/83640.png)
,
则
![](http://thumb.1010pic.com/pic5/latex/83641.png)
,
故
![](http://thumb.1010pic.com/pic5/latex/83642.png)
=
![](http://thumb.1010pic.com/pic5/latex/83643.png)
,
注意到f(n)>0,所以f(n+1)>f(n).
特别地
![](http://thumb.1010pic.com/pic5/latex/78454.png)
,从而2T
n-log
2(2a
n+1)=log
2f(n)>0.
所以2T
n>log
2(2a
n+1),n∈N
*.
(Ⅲ)易得
![](http://thumb.1010pic.com/pic5/latex/531454.png)
.
注意到a
8=8,则有
![](http://thumb.1010pic.com/pic5/latex/531455.png)
,
即
![](http://thumb.1010pic.com/pic5/latex/531456.png)
,整理得3
m-3
m-d=8.①
当m≥d时,由①得3
m-d(3
d-1)=8.
因为m,d∈N
*,所以m=d=2.
当m<d时,由①得3
d-1=8•3
d-m.②
因为m<d,故②式右边必是3的倍数,而左边不是3的倍数,所以②式不成立,
即当m<d时,不存在m,d∈N
*,使得①式成立.
综上所述,存在正整数m=d=2,
使得
![](http://thumb.1010pic.com/pic5/latex/531457.png)
成立.
分析:(Ⅰ)由题设条件可知
![](http://thumb.1010pic.com/pic5/latex/78441.png)
.所以a
n+2-a
n=2(n∈N
*).由此可以导出a
n=n(n∈N
*).
(Ⅱ)由
![](http://thumb.1010pic.com/pic5/latex/78438.png)
,得
![](http://thumb.1010pic.com/pic5/latex/83633.png)
,
![](http://thumb.1010pic.com/pic5/latex/83634.png)
,故
![](http://thumb.1010pic.com/pic5/latex/78446.png)
.从而
![](http://thumb.1010pic.com/pic5/latex/83635.png)
.由此入手能够证明2T
n>log
2(2a
n+1),n∈N
*.
(Ⅲ)由题意知
![](http://thumb.1010pic.com/pic5/latex/531454.png)
.a
8=8,所以
![](http://thumb.1010pic.com/pic5/latex/531455.png)
,由此入手能够推导出存在正整数m=d=2,使得
![](http://thumb.1010pic.com/pic5/latex/531457.png)
成立.
点评:本题考查数列性质的综合应用,解题时要认真审题,注意挖掘题设中的隐含条件.