Majorana neutrino masses and neutrino oscillations

We examine some patterns of the Majorana neutrino mass matrix which are compatible with the phenomenological lepton flavor mixing matrix and non-observation of neutrinoless double beta decay. Imposing (Formula presented) for the Majorana neutrino mass matrix in the leading order, we obtain a relationship between the solar mixing angle and the neutrino masses (Formula presented) and (Formula presented) Additional possible texture zeros are assigned to the mass matrix so as for the nonvanishing (Formula presented) to be predictable in terms of neutrino masses. We also show how three neutrino masses can be predicted from the solar mixing angle and the experimental results of (Formula presented) and (Formula presented) in this framework, and we discuss the naturality of the forms of the mass matrix found in our work.