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已知数列{an}的前n项和为Sn,且满足a1=1,tSn-(2t+1)Sn-1=t,其中t...
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已知数列{a
n}的前n项和为S
n,且满足a
1=1,tS
n-(2t+1)S
n-1=t,其中t>0,n∈N﹡,n≥2.
(Ⅰ)求证:数列{a
n}是等比数列;
(Ⅱ)设数列{a
n}的公比为f(t)数列{b
n}满足b
1=1,b
n=f(
)(n≥2),求数列{b
n}的通项公式;
(Ⅲ)在(Ⅱ)的条件下,若t=1,数列{b
n}的前n项和为T
n,试比较a
n和T
n的大小关系.
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已知数列{an}的前n项和为Sn,且满足a1=1,tSn-(2t+1)Sn-1=t,其中t>0,n∈N﹡,n≥2.
(Ⅰ)求证:数列{an}是等比数列;
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