Question Number 30189 by abdo imad last updated on 17/Feb/18
$${find}\:{lim}_{{n}\rightarrow\infty} \:\:{n}^{−\mathrm{4}} \:\prod_{{k}=\mathrm{1}} ^{\mathrm{2}{n}} \:\left({n}^{\mathrm{2}} \:+{k}^{\mathrm{2}} \right)^{\frac{\mathrm{1}}{{n}}} \:?. \\ $$