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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