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#b2ce8c88-b25a-45d7-afcb-829d6981f1d3中等fill_compute数列求和方法数列

9.(2023•深圳模拟)已知数列{an}\{a_{n}\}的前nn项和为SnS_{n},满足:2an+1=an+an+2(nN)2a_{n+1}=a_{n}+a_{n+2}({n\in N^{*}}),且a3a_{3}a7a_{7}为方程x218x+65=0x^{2}-18x+65=0的两根,且a7>a3a_{7}>a_{3}.若对于任意nNn\in N^{*},不等式2nan(4λ)>(an1)22^{n}a_{n}(4-\lambda )>({a_{n}-1})^{2}恒成立,则实数λ\lambda的取值范围为 ___(,185)({-\infty ,\frac{18}{5}})___.