The Values of Modular Functions and Modular Forms

Choi, So Young

Canadian mathematical bulletin, Tome 49 (2006) no. 4, pp. 526-535

Résumé

Let ${{\Gamma }_{0}}$ be a Fuchsian group of the first kind of genus zero and $\Gamma$ be a subgroup of ${{\Gamma }_{0}}$ of finite index of genus zero. We find universal recursive relations giving the ${{q}_{r}}$ -series coefficients of ${{j}_{0}}$ by using those of the ${{q}_{{{h}_{s}}}}$ -series of $j$ , where $j$ is the canonical Hauptmodul for $\Gamma$ and ${{j}_{0}}$ is a Hauptmodul for ${{\Gamma }_{0}}$ without zeros on the complex upper half plane $\mathfrak{H}\left( \text{here}\,\,{{q}_{\ell }}\,:=\,{{e}^{2\pi iz/\ell }} \right)$ . We find universal recursive formulas for $q$ -series coefficients of any modular form on $\Gamma _{0}^{+}\left( p \right)$ in terms of those of the canonical Hauptmodul $j_{p}^{+}$ .

Détail

DOI : 10.4153/CMB-2006-050-4

Mots-clés : 10D12, 11F11

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