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已知数列{an}中,a1=2,a2=4,an+1=3an-2an-1(n≥2,n∈N*)....
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已知数列{a
n}中,a
1=2,a
2=4,a
n+1=3a
n-2a
n-1(n≥2,n∈N
*).
(Ⅰ)证明数列{a
n+1-a
n}是等比数列,并求出数列{a
n}的通项公式;
(Ⅱ)记
,数列{b
n}的前n项和为S
n,求使S
n>2010的n的最小值.
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