## The modular curve $X_{33b}$

Curve name $X_{33b}$
Index $24$
Level $8$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $\left[ \begin{matrix} 5 & 0 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 5 & 5 \\ 4 & 1 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 4 & 3 \end{matrix}\right]$
Images in lower levels
 Level Index of image Corresponding curve $2$ $3$ $X_{6}$ $4$ $6$ $X_{13}$
Meaning/Special name
Chosen covering $X_{33}$
Curves that $X_{33b}$ minimally covers
Curves that minimally cover $X_{33b}$
Curves that minimally cover $X_{33b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by $y^2 = x^3 + A(t)x + B(t), \text{ where}$ $A(t) = -108t^{8} - 2592t^{6} - 21168t^{4} - 62208t^{2} - 27648$ $B(t) = -432t^{12} - 15552t^{10} - 220320t^{8} - 1524096t^{6} - 5059584t^{4} - 5971968t^{2} + 1769472$
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 39x - 92$, with conductor $576$
Generic density of odd order reductions $289/1792$