A Maass form of weight 0 on a subgroup $$\Gamma$$ of $$\GL_{2}(\R)$$ is a smooth, square-integrable, automorphic eigenfunction of the Laplace-Beltrami operator $\Delta$. In other words, $$f\in C^\infty(\mathcal{H}),\quad f\in L^2(\Gamma\backslash{\mathcal H}),\quad f(\gamma z)=f(z)\ \forall\gamma\in\Gamma,\quad (\Delta+\lambda)f(z)=0 \textrm{ for some } \lambda \in \C.$$
The database contains 14995 Maass forms of weight 0 on $\Gamma_0(N)$ for $N$ in the range from 1 to 997.