13-14高一下·重庆·阶段练习
1 . 将一个等差数列依次写成下表:
第1行:2
第2行:5 8 11
第3行:14 17 20 23 26
………………………………………………
第
行:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30e843a95617ad24ea4e789a0cdc5912.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68c82be573157fd2c8068cb000505b43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aec8aa05d77a638e99494af9dfc0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907e338a2cd8381353173126753e2415.png)
………………![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2814549b2e9f30007ab2d811dd9adf9.png)
(其中
表示第
行中的第
个数)
那么第
行的数的和是_________________ .
第1行:2
第2行:5 8 11
第3行:14 17 20 23 26
………………………………………………
第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30e843a95617ad24ea4e789a0cdc5912.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68c82be573157fd2c8068cb000505b43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aec8aa05d77a638e99494af9dfc0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907e338a2cd8381353173126753e2415.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392546a6637cb8faf9f356f4739cd7e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2814549b2e9f30007ab2d811dd9adf9.png)
(其中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee641d39bc70aa40e611fcfc6b78f30b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7600d2cfbdc6146db96cc545706004f6.png)
那么第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次