来自丁志刚的问题
已知数列{an}满足a1=1,an+1•an=2n(n∈N*),则S2012=___.
已知数列{an}满足a1=1,an+1•an=2n(n∈N*),则S2012=___.
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2020-11-1806:58
已知数列{an}满足a1=1,an+1•an=2n(n∈N*),则S2012=___.
已知数列{an}满足a1=1,an+1•an=2n(n∈N*),则S2012=___.
∵数列{an}满足a1=1,an•an+1=2n,n∈N*∴n=1时,a2=2,∵an•an+1=2n,∴n≥2时,an•an-1=2n-1,∴an+1an-1=2,∴数列{an}的奇数列、偶数列分别成等比数列,∴S2012=1-210061-2+2(1-21006)1-2=3×21006-3.故答案...