名校
1 . 某人写了
封不同的信和
个相应的不同信封,设这
封信全都装错信封的方法有
种,易知
,
,递推公式为
经过变形构造化简计算,可得它的通项公式为
,其中
为自然对数的底数,
表示不大于
的最大整数,
.则
=______
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1bae03ee4ac75dacfb026290e4207dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f966272f7781790ff27e40db6b525253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/656945f0860b6453f495356b597a4284.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb8167bd864bba47020865f6e0345f8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/096d0fb92f2d4568302061ba70a367f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/041a7c8fc017f596542c5e6ec7d1c40b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4f5908d6a1217e493ed7586b6964dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d864b9654e7104a3b43e7230af887280.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5da4cd81500bdb43118150dbdb1541e6.png)
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名校
2 . 已知数列
中,
,则数列
的前5项和为_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f81d7a787b4e355f132f4fd8cfc652c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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3 . 在数列
中,若
,则2014是这个数列的第______ 项.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ab4ad049f59b28b6f434b5933af5a8.png)
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2019-11-09更新
|
175次组卷
|
2卷引用:黑龙江省鹤岗市第一中学2019-2020学年高一下学期期末考试数学(文)试题
名校
4 . 若数列{
}的前n项和为
,则
=___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee3e1619fc8f1dd4593039256c55596a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/010a9ae3c4c9d3d0a2ad40ce15e98dba.png)
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2019-05-23更新
|
1950次组卷
|
5卷引用:黑龙江省哈尔滨市第三十二中学校2021-2022学年高三上学期期中考试理科数学试题
名校
5 . 已知数列
的通项公式是
,则它的前
项和为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09fd65eb622648669a0a9575e47b1a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
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