Instead of right-handed neutrino singlets, the standard model is extended to include lepton triplets $(Sigma^+, Sigma^0, Sigma^-)$. Each quark and lepton family may now transform under an anomaly-free $U(1)_X$ gauge symmetry, known already for many years. A new sequential application is presented, using just the one Higgs doublet of the standard model, together with two $U(1)_X$ Higgs singlets. The resulting structure has hierarchical quark and lepton masses, as well as a viable seesaw neutrino mass matrix.
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