$\begin{array}{1 1} \large\frac{n(n+1)(n+2)}{3} \\ \large\frac{n(n+1)(n+2)}{6} \\ \large\frac{n(n+1)(2n+1)}{3} \\ \large\frac{n(n+1)(n+2)}{2} \end{array} $