A gas consists of identical hydrogen like atoms in the lowest (ground) energy level A, and some atoms in a particular upper (excited) energy level B, but there are no atoms in any other energy level in the gas. The atoms of the gas make transitions to a higher energy level by absorbing monochromatic light of photon energy 2.55 eV. Subsequently, the atoms emit radiation of only six different photon energies. Some of the emitted photons have energy of 2.55 eV, some have more energy, and some have energy less than 2.55 eV. The ionization energy for the gas atoms is 3.4n eV, where n is an integer. Find n.