Covariants of binary sextics and vector-valued Siegel modular forms of genus two

@article{Clry2016CovariantsOB,
  title={Covariants of binary sextics and vector-valued Siegel modular forms of genus two},
  author={Fabien Cl{\'e}ry and Carel Faber and Gerard van der Geer},
  journal={Mathematische Annalen},
  year={2016},
  volume={369},
  pages={1649-1669}
}
We extend Igusa’s description of the relation between invariants of binary sextics and Siegel modular forms of degree 2 to a relation between covariants and vector-valued Siegel modular forms of degree 2. We show how this relation can be used to effectively calculate the Fourier expansions of Siegel modular forms of degree 2. 

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