若数列{an}满足a1+3a2+3²a3+···+3^n-1an=(n+1)/3,则an=?

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若数列{an}满足a1+3a2+3²a3+···+3^n-1an=(n+1)/3,则an=?
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若数列{an}满足a1+3a2+3²a3+···+3^n-1an=(n+1)/3,则an=?
若数列{an}满足a1+3a2+3²a3+···+3^n-1an=(n+1)/3,则an=?

若数列{an}满足a1+3a2+3²a3+···+3^n-1an=(n+1)/3,则an=?
a1+3a2+3²a3+···+3^(n-2)a(n-1)+3^(n-1)an=(n+1)/3
a1+3a2+3²a3+···+3^(n-2)a(n-1) =(n-1+1)/3=n/3
2个式子相减
3^(n-1)an=1/3
an=1/(3^n)

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