Rydberg's published formula was ± ± n N 0 = 1 ( m 1 + μ μ 1 ) 2 − − 1 ( m 2 + μ μ 2 ) 2 where n is the observed wavenumber, N 0 is a constant for all spectral series and elements, and the remaining values, m 1 , μ μ 1 , m 2 , μ μ 2 are integers indexing the various lines. When Bohr analyzes his model for the atom he writes ν ν = 2 π π 2 m e 4 h 3 ( 1 τ τ 2 2 − − 1 τ τ 1 2 ) where he uses frequency ν ν (proportional to wavenumber). Thus he has been able to compute the value of Rydberg's heuristic constant N 0 from his atom theory and set the integers μ μ 1 and μ μ 2 to zero. The effect is to predict new series corresponding to τ τ 2 = 1 in the extreme ultraviolet unknown to Rydberg.