Question Number 2843 by prakash jain last updated on 28/Nov/15
$$\mathrm{Prove}\:\mathrm{by}\:\mathrm{mathematical}\:\mathrm{induction} \\ $$$${n}\left({n}+\mathrm{1}\right)\left({n}+\mathrm{2}\right)...\left({n}+{r}−\mathrm{1}\right)\:\mathrm{is}\:\mathrm{divible}\:\mathrm{by}\:{r}! \\ $$$$ \\ $$$${n},{r}\in\mathbb{N}. \\ $$
Commented by 123456 last updated on 28/Nov/15
$$\mathbb{N}=\left\{\mathrm{0},\mathrm{1},\mathrm{2},...\right\} \\ $$$$\mathrm{or} \\ $$$$\mathbb{N}=\left\{\mathrm{1},\mathrm{2},\mathrm{3},...\right\} \\ $$$$??? \\ $$
Commented by prakash jain last updated on 28/Nov/15
$$\mathbb{N}=\left\{\mathrm{1},\mathrm{2},\mathrm{3},...\right\} \\ $$