设数列{an}满足a1+3 a2+3^2 a3+……+3^n-1 an=n/3,a属于N* 求数列{an}的通项谢谢大家呐```

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设数列{an}满足a1+3 a2+3^2 a3+……+3^n-1 an=n/3,a属于N*       求数列{an}的通项谢谢大家呐```
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设数列{an}满足a1+3 a2+3^2 a3+……+3^n-1 an=n/3,a属于N* 求数列{an}的通项谢谢大家呐```
设数列{an}满足a1+3 a2+3^2 a3+……+3^n-1 an=n/3,a属于N* 求数列{an}的通项
谢谢大家呐```

设数列{an}满足a1+3 a2+3^2 a3+……+3^n-1 an=n/3,a属于N* 求数列{an}的通项谢谢大家呐```
an=1/3^n

用作差法
a1+3a2+3^2a3+...………………+3^(n-1)an=n/3
a1+3a2+3^2a3+...+3^(n-2)a(n-1) =(n-1)/3
两式相减
得:3^(n-1)an=1/3
所以 an=1/3^n

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