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在数列{an}中,已知a1=1,且数列{an}的前n项和Sn满足4Sn+1-3Sn=4,n...
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在数列{a
n}中,已知a
1=1,且数列{a
n}的前n项和S
n满足4S
n+1-3S
n=4,n∈N
*.
(1)证明数列{a
n}是等比数列;
(2)设数列{na
n}的前n项和为T
n,若不等式
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H7BPQKGDDh+wHZz6BJE/X8/sszeDOGIAAAAASUVORK5CYII=
)
对任意的n∈N
*恒成立,求实数a的取值范围.
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