已知数列{an}的前n项和为Sn=-n2+n,数列{bn}满足bn=2an,求l 发布时间:2017-05-02 00:40 │ 来源:www.tikuol.com 题型:解答题 问题: 已知数列{an}的前n项和为S n=-n2+n,数列{bn}满足b n=2an,求limn→ω(b1+b2+…+bn).