1 . 正整数数列
满足
,
满足
,
.在
中两数列的公共项的个数是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/204599d8ea20f6c9067108e219408e77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da1295a23c862d4015738ea74a68de07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd4613271f782a90ab580131d09d03d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31acd0e41081a835a3a4aafb0e1bf8a4.png)
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2 . 若三个角
、
、
成等差数列,公差为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbcec425e0dbc39b16e8c47d0ef25461.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbcec425e0dbc39b16e8c47d0ef25461.png)
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3 . 如图,将一个边长为1的正三角形分成四个全等的正三角形,第一次挖去中间的一个小三角形,将剩下的三个小正三角形,再分别从中间挖去一个小三角形,保留它们的边,重复操作以上做法,得到的集合为谢尔宾斯基垫.
设
是第n次挖去的小三角形面积之和(如
是第1次挖去的中间小三角形面积,
是第2次挖去的三个小三角形面积之和),则前n次挖去的所有小三角形面积之和的值为____________________ .
设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fb8642f2997146847ea9ee1a29bb2dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/035a5a88e7e2d6ef2b47d992412a1f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eb960b00b7d4985d659b62eb74f470a.png)
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4 . 已知△ABC的三个角A、B、C成等差数列,对应的三边为a、b、c,且a、c、
成等比数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fb44237b19f85aca4bb65076f05a3f3.png)
___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e80d16679404420054744c18108de409.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fb44237b19f85aca4bb65076f05a3f3.png)
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5 . 把1,2,…,
按照顺时针螺旋方式排成n行n列的表格
,第一行是1,2,…,n.例如:
.设2018在
的第i行第j列,则(i,j)=___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ceef1abeeef220b4fe5f7d96feedd90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/330e0b571a2560d200094863f0bff46f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00136ab4fd69ba9c28b47cd38442dc3a.png)
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6 . 设
是整数等差列,n为偶数.甲:它的各项之和
是偶数.乙:它的公差d是偶数.那么甲是乙的( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbec176b6facae13391ac55e4e15ec4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
A.充分条件,也是必要条件. |
B.充分条件,但非必要条件. |
C.必要条件,但非充分条件. |
D.既非充分条件,也非必要条件. |
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7 . 等差数列
满足
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9e61cea2dd2e030616c36bbcd2c8b49.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f41de35c0f374b4c208a7c44e34b8d5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/467378eaf847794778899a0caa9bd062.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9e61cea2dd2e030616c36bbcd2c8b49.png)
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8 . 2014把椅子排成一圈,有n个人坐在椅子上,使得再有一人坐入时,总与原来的n个人中的一人坐在相邻的椅子上.则n的最小值为________ .
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9 . 已知实数
满足
,
,其中,n=1,2,…,2015.若
,且
,求以下表达式的值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1900f7225988d7214068cebe0c4e5dea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae92c46135dca4eb8093066585691bea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3b271c9594d0e4b9f607def5b70ebf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6260ccd4e29052a9ced31310c2ba406d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d30185b4ce55ad9b0ef97ed2a9240626.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a243cf192fc4f0e815ddf8a03a572aff.png)
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10 . 已知数列
均为等差数列,且
.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/312c1ff2feb1b980280e8e58c105982d.png)
_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a1709665198a9a3dfab2f7d671cd4ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6bfd24b19a4acad69103d946eeb322.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/312c1ff2feb1b980280e8e58c105982d.png)
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