What is the wavelength of the most energetic photon emitted in the Balmer series of the Hydrogen atom  

For Balmer series, 
$\frac{1}{\mathrm{\lambda }}=\mathrm{R}\left[\frac{1}{2^2}-\frac{1}{{\mathrm{n}}^2}\right]$; where      ….(i)
n = 3,4,5
By putting in equation (i), we obtain the series limit of the Balmer series 
$\frac{1}{\mathrm{\lambda }}=\mathrm{R}\left[\frac{1}{2^2}-\frac{1}{{\mathrm{\infty }}^2}\right]\text{ or }\mathrm{\lambda }=364.5\mathrm{nm}$