已知等差数列{an}满足a5=16,a7=22,正项等比数列{bn}的前n项和为Sn,满足S6=5S4-4S2,且b2=a1.
(1)求{an}和{bn}的通项公式;
(2)是否存在n使得
,若存在,求出所有n的值;若不存在,请说明理由.
(1)求{an}和{bn}的通项公式;
(2)是否存在n使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63516a8055761db59b2af52ff3b90832.png)
2022·江苏南通·模拟预测 查看更多[2]
更新时间:2022-05-25 11:32:41
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