\[{\cal L}_{k}^{(n)}(s)=\frac{\sum_{j=0}^{k}(-1)^{j}\genfrac{(}{)}{0.0pt}{}{k}{j%
}c_{j,k,n}\ifrac{s_{n+j}}{a_{n+j+1}}}{\sum_{j=0}^{k}(-1)^{j}\genfrac{(}{)}{0.0%
pt}{}{k}{j}c_{j,k,n}/a_{n+j+1}},\]