已知数列an满足a1+3a2+3²a3+……+3的n-1次方an=n/2,则an=
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![已知数列an满足a1+3a2+3²a3+……+3的n-1次方an=n/2,则an=](/uploads/image/z/745626-66-6.jpg?t=%E5%B7%B2%E7%9F%A5%E6%95%B0%E5%88%97an%E6%BB%A1%E8%B6%B3a1%2B3a2%2B3%26%23178%3Ba3%2B%E2%80%A6%E2%80%A6%2B3%E7%9A%84n-1%E6%AC%A1%E6%96%B9an%3Dn%2F2%2C%E5%88%99an%3D)
已知数列an满足a1+3a2+3²a3+……+3的n-1次方an=n/2,则an=
已知数列an满足a1+3a2+3²a3+……+3的n-1次方an=n/2,则an=
已知数列an满足a1+3a2+3²a3+……+3的n-1次方an=n/2,则an=
先把n=1代入,可得a1=1/2,再把n=2再入,可得3a2=1/2,n每增加1,多一项,且和多1/2,所以每一项都是1/2,所以3的n-1次方an=1/2,an=1/(2*3的n-1次方).