G
guchannguyen@gmail.com
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
Tim so nguyen duong chan n biet
[TEX]\frac{1}{2!(n-2)!}+\frac{1}{4!(n-4)!}+\frac{1}{6!(n-6)!}+...+\frac{1}{(n-2)!2!}=\frac{2^2013 -2}{n!}[/TEX]
2^(2013) nha
[TEX]\frac{1}{2!(n-2)!}+\frac{1}{4!(n-4)!}+\frac{1}{6!(n-6)!}+...+\frac{1}{(n-2)!2!}=\frac{2^2013 -2}{n!}[/TEX]
2^(2013) nha