Question Number 128065 by 0731619177 last updated on 04/Jan/21
Commented by mnjuly1970 last updated on 04/Jan/21
$${lim}_{{n}\rightarrow\infty\:\:\:} \underset{{k}=\mathrm{1}\:} {\overset{\infty} {\sum}}\frac{\mathrm{1}}{{k}^{\mathrm{2}} }=\frac{\pi^{\mathrm{2}} }{\mathrm{6}} \\ $$$${lim}_{{n}\rightarrow\infty} \left(\underset{{k}=\mathrm{1}} {\overset{{n}} {\sum}}\frac{\mathrm{1}}{{k}}\:\:−{ln}\left({n}\right)\right)=\gamma\:\left({euler}−\:{constant}\right) \\ $$$${lim}_{{x}\rightarrow\infty} \left(\frac{\sqrt[{{x}}]{{x}!}}{{x}}\right)=\frac{\mathrm{1}}{{e}} \\ $$$$\therefore\:\:\:\:{ans}:\:\:\left[\:\left(\frac{\mathrm{1}}{{e}}\right)^{\gamma} \:\right]^{\frac{\pi^{\mathrm{2}} }{\mathrm{6}}} =\left(\frac{\mathrm{1}}{{e}}\right)^{\frac{\gamma\pi^{\mathrm{2}} }{\mathrm{6}}} \\ $$