\newcommand{\combination}[2]{ \left( \begin{array}{c} #1 \\ #2 \end{array} \right ) }
 \cdots = \lim_{t \rightarrow 0} \combination{n+1}{1}\frac{1}{n}= \lim_{t \rightarrow 0} \frac{n+1}{n} ~, ~\forall n \in N