已知集合A={a
1,a
2,…,a
n}中的元素都是正整数,且a
1<a
2<…<a
n,对任意的x,y∈A,且x≠y,都有
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102429882397064/SYS201311031024298823970022_ST/0.png)
.
(1)求证:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102429882397064/SYS201311031024298823970022_ST/1.png)
;(提示:可先求证
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102429882397064/SYS201311031024298823970022_ST/2.png)
(i=1,2,…,n-1),然后再完成所要证的结论.)
(2)求证:n≤11;
(3)对于n=11,试给出一个满足条件的集合A.
考点分析:
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