数列an满足a1+2a2+3a3+...+nan=n(n+1)(n+2) 求通项an急,谢谢解惑

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数列an满足a1+2a2+3a3+...+nan=n(n+1)(n+2) 求通项an急,谢谢解惑
数列an满足a1+2a2+3a3+...+nan=n(n+1)(n+2) 求通项an
急,谢谢解惑

数列an满足a1+2a2+3a3+...+nan=n(n+1)(n+2) 求通项an急,谢谢解惑
a1+2a2+3a3+...+nan=n(n+1)(n+2)
a1+2a2+3a3+...+(n-1)an-1=(n-1)n(n+1)
nan=3n(n+1)
an=3(n+1)

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