Curve name  $X_{8b}$  
Index  $12$  
Level  $4$  
Genus  $0$  
Does the subgroup contain $I$?  No  
Generating matrices  $ \left[ \begin{matrix} 1 & 0 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 2 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 1 & 2 \\ 2 & 1 \end{matrix}\right]$  
Images in lower levels 


Meaning/Special name  
Chosen covering  $X_{8}$  
Curves that $X_{8b}$ minimally covers  
Curves that minimally cover $X_{8b}$  
Curves that minimally cover $X_{8b}$ and have infinitely many rational points.  
Model  $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = 108t^{6}  108t^{4} + 540t^{2}  324\] \[B(t) = 432t^{9}  5184t^{7} + 12960t^{5}  12096t^{3} + 3888t\]  
Info about rational points  
Comments on finding rational points  None  
Elliptic curve whose $2$adic image is the subgroup  $y^2 + xy = x^3  x^2  12546x + 173047$, with conductor $1089$  
Generic density of odd order reductions  $9/56$ 