已知数列{an}（n∈N*）的前n项和Sn=-n2+1，则a6=（） A．11

发布时间：2017-05-04 14:04 │ 来源：www.tikuol.com

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问题：

已知数列{a_n}（n∈N^*）的前n项和Sn=-n2+1，则a₆=（　　）

A．11

B．-11

C．13

D．-13

考点：数列的概念及简单表示法

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