已知数列a1=2,an+an-1=2^n+2^n-1,求log2(s2012+2)=?

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已知数列a1=2,an+an-1=2^n+2^n-1,求log2(s2012+2)=?
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已知数列a1=2,an+an-1=2^n+2^n-1,求log2(s2012+2)=?
已知数列a1=2,an+an-1=2^n+2^n-1,求log2(s2012+2)=?

已知数列a1=2,an+an-1=2^n+2^n-1,求log2(s2012+2)=?
an+a(n-1) =2^n+2^(n-1)
S2012=a1+a2+...+a2012
=(a1+a2)+(a3+a4)+...+(a2011+a2012)
=(2^2+2^1)+(2^4+2^3)+...+(2^2012+2^2011)
= 2(2^2012-1)/(2-1)
= 2^2013 -2
S2012+2 =2^2013
log(2)}{S2012+2} = 2013