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arXiv · 2603.16109

Analogue of the theta group $\Gamma_{\theta},$ II

Kazuhide Matsuda
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Abstract

In this series of papers, we introduce higher level versions of the theta group $\Gamma_{\theta}.$ In this paper, we treat the theta group of level $5$, $\Gamma_{\theta,5},$ and construct modular forms on $\Gamma_{\theta,5}$. Moreover we compute their multiplier systems. For this purpose, we derive transformation formula of theta function with characteristics.

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Kazuhide Matsuda. 2026-03-17. Analogue of the theta group $\Gamma_{\theta},$ II. https://arxiv.org/abs/2603.16109

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