How to compute series expansion while keeping the factorials in the expression?

A little more information about what you want to do would be useful. Posting a worksheet showing the problem would be even better (Top right: Use advanced editor, then bottom left to attach a worksheet).

sin(x)=x-x^3/3!+x^5/5!...

not

sin(x)=x-x^3/6+x^5/120...

Thanks,

Robert Otome