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#4bd8533d-f0a5-4c83-aece-47307a962726中等fill_compute数列求和方法数列

8.(2023•黑龙江一模)已知数列{an}\{a_{n}\}nn项和Sn=n2{S_n}={n^2},数列{bn}\{b_{n}\}满足bn=1anan+1,nN,n1;Tn{b_n}=\frac{1}{{a_n}\cdot {a_{n+1}}},n\in {N},n\geqslant 1;{T_n}为数列{bn}\{b_{n}\}的前nn项和.若对任意的nNn\in Nn1n\geqslant 1,不等式λTn<n+9(1)n\lambda {T_n}<n+9\cdot {(-1)^n}恒成立,则实数λ\lambda的取值范围为 ___(,24)(-\infty ,-24)___.