给定数列{An}满足An=[lg(n+2)]/[lg(n+1)] n∈N*,定义乘积A1*A2*~~~~*Ak为整数时的k叫做希望数,则[1,2010

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给定数列{An}满足An=[lg(n+2)]/[lg(n+1)] n∈N*,定义乘积A1*A2*~~~~*Ak为整数时的k叫做希望数,则[1,2010
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an=[lg(n+2)]/[lg(n+1)]A1A2...Ak=(lg3/lg2)(lg4/lg3)...[lg(k+2)/lg(k+1)]=[lg(k+2)/lg2],要乘积的结果是整数,只有k+2是2的乘方.令k+2=2^m,1≤k≤20103≤k+2≤20123≤2^m≤20122≤m≤10共有9个.此时k=2,6,14,30,62,...