$\displaystyle \left(\frac{1}{1}\right)$+$\displaystyle \left(\frac{1+2}{1.2}\right)$+$\displaystyle \left(\frac{1+2+3}{1.2.3}\right)$+$\displaystyle \left(\frac{1+2+3+4}{1.2.3.4}\right)$+...................

find out the $\displaystyle \bigcup r$. and put it into partial fraction. Through this $\displaystyle \sum_{r=1}^{\propto} \bigcup r$=$\displaystyle \frac{3e}{2}$ In this case i write the $\displaystyle \bigcup{r}$

like this $\displaystyle \bigcup r$=$\displaystyle \frac{\sum_{r=1}^{\propto}}{r!}$ Then how can i partial fraction.>>>>>>