The number of possible spectral lines emitted when electron in n = 4 Bohr orbit reaches to n = 1 Bohr orbit

The possible spectral emissions correspond to the transfer n = 4 to n = 3, n = 4 to n =2, n = 4 to n= l, n=3 to n=2, n=3 to n =l and n = 2 to n = 1. There are 6 emissions.