# Table:Delta hk

 $\mathbb{T}=$ $h_k(t,s;\mathbb{T})=$ $\mathbb{R}$ $\dfrac{(t-s)^k}{k!}$ $\mathbb{Z}$ $\displaystyle{t-s \choose k} = \dfrac{(t-s)!}{k! (t-s-k)!}$ $h\mathbb{Z}$ $\dfrac{1}{k!} \displaystyle\prod_{\ell=0}^{k-1}(t-\ell h-s)$ $\mathbb{Z}^2$ $\overline{q^{\mathbb{Z}}}, q > 1$ $\displaystyle\prod_{n=0}^{k-1} \dfrac{t-q^ns}{\sum_{i=0}^n q^i}$ $\overline{q^{\mathbb{Z}}}, q < 1$ $\mathbb{H}$