Gamma 1 level structure on a complex lattice (source code)

= Gamma 1 level structure on a complex lattice
{c}
{title2=$\Gamma_1(N)$-level structure}

A Gamma 1 level structure on a complex lattice $\Lambda$ is a point of exact order $N$ in $\mathbb C/\Lambda$. Similarity classes of such pairs are parametrized by $\Gamma_1(N)\backslash\mathfrak h$.