Question Number 218767 by SdC355 last updated on 15/Apr/25

$$\underset{\ell\in\left(−\infty,\infty\right)} {\sum}\:{J}_{\ell} \left({z}\right)=?? \\ $$
Answered by MrGaster last updated on 15/Apr/25

$$\underset{\ell\in\left(−\infty,\infty\right)} {\sum}{J}_{\ell} \left({z}\right)=\mathrm{exp}\left(\frac{{z}}{\mathrm{2}}\left(\mathrm{1}−\frac{\mathrm{1}}{\mathrm{1}}\right)\right)=\mathrm{exp}\left(\mathrm{0}\right)=\mathrm{1} \\ $$