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We compile from literature the broadband SEDs of twelve TeV blazars observedsimultaneously or quasi-simultaneously with Fermi/LAT and other instruments.Two SEDs are available for each of the objects and the state is identified as alow or high state according to its flux density at GeV/TeV band. The observedSEDs of BL Lac objects (BL Lacs) are fitted well with the synchrotron +synchrotron-self-Compton (syn+SSC) model, whereas the SEDs of the two flatspectrum radio quasars (FSRQs) need to include the contributions of externalCompton scattering. In this scenario, it is found that the Doppler factor deltaof FSRQs is smaller than that of BL Lacs, but the magnetic field strength B ofFSRQs is larger than that of BL Lacs. The increase of the peak frequency of theSEDs is accompanied with the increase of the flux for the individual sources,which seems opposite to the observational phenomena of the blazar sequence. Werefer this phenomenon to blazar anti-sequence of spectral variability forindividual TeV blazars. However, both the blazar sequence from FSRQs to BL Lacsand blazar anti-sequence of the spectral variability from low state to highstate are accompanied by an increase of the break Lorentz factor of theelectron's spectrum gamma_b and a decrease of B. We propose a model in whichthe mass accretion rate is the driving force behind both the blazar sequencefor ensembles of blazars and the blazar anti-sequence for individual blazars.Specifically we suggest that the differences in mass accretion rate ofdifferent blazars produce the observed blazar sequence, but \Delta M in eachblazar results in the observed blazar anti-sequence.

Blazar Anti-Sequence of Spectral Variability for Individual TeV Blazars