Flipped SU(6) unification of the sequential SU(3)c x SU(3)L x U(1)X model

We propose to partially unify the sequential SU(3)c x SU(3)L x U(1)X model (with fi = 1/ p ) into the ffiffi3 flipped SU(6) model with the gauge group SU(6) x U(1)K. Gauge anomaly cancellation can easily be satisfied. We discuss the relevant Higgs sector, the low energy 331 model spectrum, and the unification of SU(3)c and SU(3)L gauge couplings. Neutrino mass generation and successful gauge coupling unification can set lower/upper bounds on the 331 breaking scale. The partial proton decay lifetime of various channels, for example, the p - e+x-0 channel, in flipped SU(6) GUT are discussed. We find that certain parameter region with M331 similar to 1015 GeV of case II (for case with M331 scale similar to H3;8 Higgs field) can predict a partial proton lifetime of order 1034 years for p - e+x-0 mode, which can be tested soon by future DUNE and Hyper-Kamiokande experiments.