what is the value of $\sum_{i=1}^ni^m$

Question

I know that $$\sum_{i=1}^ni=\frac{n(n+1)}{2}$$ can be proved using Gauss method , and $$\sum_{i=1}^ni^2=\frac{(n^2+n)(2n+1)}{6}$$ can be proved using induction method, what is the value of $$\sum_{i=1}^ni^m$$