According to the equation for the Balmer line spectrum of hydrogen, a value of n = 3 gives a red spectral line at 656.3 nm, a value of n = 4 gives a green light at 486.1 nm, and a value of n = 5 gives a blue line at 434.0 nm. According to these wavelength differences between lines in the Balmer series become smaller as n becomes larger, at what wavelength in nanometres do the lines converge.