1 . 已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7812839fa5b5a3698d26a3353881643e.png)
…,其中在第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
个1与第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0876215b2fd463d151523cd3c6b447.png)
个1之间插入
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06dd04ebe420af1816ecf77ec405ebaa.png)
若该数列的前
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6567511bb9486b2ca7452b870abd2a1f.png)
项的和为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ee1174886164109798ee5f06818e844.png)
则
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2021-07-03更新
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287次组卷
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3卷引用:全国Ⅱ卷2021届高三高考数学(理)仿真模拟试题全国Ⅱ卷2021届高三高考数学(理)仿真模拟试题(已下线)第03讲 等差数列的前n项和公式-【帮课堂】2021-2022学年高二数学同步精品讲义(人教A版2019选择性必修第二册)(已下线)专题7.2 等差数列及其前n项和(练)- 2022年高考数学一轮复习讲练测(新教材新高考)