Is there a way to express $$\sum_{k=1}^{n}{k!}$$ in a simpler way that doesn't use sums up to n ?
I've searched for this around the web and found that the subfactorial function can help with this, however, it's also defined by a sum, so this does not meet the criteria.
If you plug it in wolfram Alpha, you get an alternate expression without the subfactorial, but it has the gamma function which by definition is still a sum (integral).
http://www.wolframalpha.com/input/?i=summation+from+1+to+n+of++k+factorial+