  Extensive fractional quantum Hall effect (FQHE) has been observed in
graphene-based materials. Some of the observed fractions are anomalous in that
FQHE has not been established at these fractions in conventional GaAs systems.
One such fraction is $4/13$, where incompressibility has recently been reported
in graphene [Kumar et al., Nat. Comm. 9, 2776 (2018)]. We propose a partonic
wave function at $4/13$ and show it to be a viable candidate to describe the
Coulomb ground state. Using the effective edge theory, we make predictions for
experimentally measurable properties of the state.
