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#9a7d90c0-778e-4785-a599-363107a3f73e中等fill_compute数列求和方法数列

11.(2022秋•沙坪坝区校级期末)已知数列{an}\{a_{n}\}的通项an=13[2n(1)n]a_{n}=\frac{1}{3}[2^{n}-(-1)^{n}]bn=anan+1b_{n}=a_{n}a_{n+1},设SnS_{n}是数列{an}\{a_{n}\}的前nn项和.若bnλSn>0b_{n}-\lambda S_{n}>0对任意nNn\in N^{*}都成立,则λ\lambda的取值范围是___(,1)(-\infty ,1)___.