Abstract
We develop a new algorithm to compute a basis for \(M_k(\Gamma _0(N))\), the space of weight k holomorphic modular forms on \(\Gamma _0(N)\), in the case when the graded algebra of modular forms over \(\Gamma _0(N)\) is generated at weight two. Our tests show that this algorithm significantly outperforms a commonly used algorithm which relies more heavily on modular symbols.
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Acknowledgements
The second and third authors received funding for this project through the James Madison University Tickle Scholarship Fund, while the fourth author received support from a James Madison University College of Science and Mathematics Faculty Summer Grant.
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Communicated by A. Constantin.
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Lam, M.O., McClelland, N.S., Petty, M.R. et al. Computing bases of modular forms using the graded algebra structure. Monatsh Math 188, 121–130 (2019). https://doi.org/10.1007/s00605-018-1168-9
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DOI: https://doi.org/10.1007/s00605-018-1168-9