Question Number 100289 by Ar Brandon last updated on 26/Jun/20
$$\underset{\mathrm{n}\rightarrow\infty} {\mathrm{lim}}\underset{\mathrm{k}=\mathrm{n}} {\overset{\mathrm{2n}} {\sum}}\mathrm{sin}\left(\frac{\pi}{\mathrm{k}}\right) \\ $$$${Riemann}'{s}\:{integral}\:{may}\:{help} \\ $$