Hierarchy of fillings for FQHE in monolayer and in bilayer graphene: Explanation of $\nu =-\frac{1}{2}$ fractional quantum Hall state in bilayer graphene

The commensurability condition is applied to determine the hierarchy of fractional fillings of Landau levels in monolayer and bilayer graphene. The filling rates for FQHE in graphene are found and illustrated in the first three Landau levels. The good agreement with the experimental data is achieved. The presence of even denominator filling fractions in the hierarchy for FQHE in bilayer graphene is explained.