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#efbcbeb5-2c26-45fe-9a4f-e1b6d3cb5018简单解答题等比数列的概念与通项数列

9.设等比数列{an}\{a_{n}\}的前nn项和为SnS_{n},写出一个满足下列条件的{an}\{a_{n}\}的公比q=q=[ 2(答案不唯一) ].
a1>0a_{1}>0,②{an}\{a_{n}\}是递增数列,③S3<13a1S_{3}<13a_{1}