I am trying to calculate the Lyman-alpha wavelengths of photons emitted from different hydrogen-like atoms such as deuterium and positive helium ion 4He+, using the relation 1/λ = R*|1/ni^2 - 1/nf^2|, where R is the Rydberg constant and ni and nf are integer numbers corresponding to the initial and final energy levels, which, for Lyman-alpha wavelength, are 2 and 1, respectively. The expression for Rydberg constant is R = me/(4πħ3c)*(e2/4πε0)2. My question is: what changes in these two expressions when we are dealing with different hydrogen-like atoms?replace electron mass me with new reduced mass μ? atomic number Z (but it is not included in any of the two expressions)? Any help will be appreciated!