Can anyone tell me how

$\displaystyle \sum_{n=1}^{\infty }\frac{(-1)^{n}}{n3^{n}}(2-5)^{n}=\sum_{n=1}^{\infty }\frac{1}{n}$ ?

and also how to get this expression typed in LaTex to appear correctly?

[tex] \sum_{n=1}^{\infty }\frac{(-1)^{n}}{n3^{n}}(2-5)^{n}=\sum_{n=1}^{\infty }\frac{1}{n}[/tex]