The modular curve $X_{76b}$

Curve name $X_{76b}$
Index $48$
Level $8$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 5 & 5 \\ 2 & 3 \end{matrix}\right], \left[ \begin{matrix} 1 & 1 \\ 4 & 3 \end{matrix}\right], \left[ \begin{matrix} 1 & 0 \\ 4 & 1 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $12$ $X_{23}$
Meaning/Special name
Chosen covering $X_{76}$
Curves that $X_{76b}$ minimally covers
Curves that minimally cover $X_{76b}$
Curves that minimally cover $X_{76b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -270t^{12} + 3888t^{11} + 52272t^{10} + 129600t^{9} - 64800t^{8} - 870912t^{7} - 2225664t^{6} + 3483648t^{5} - 1036800t^{4} - 8294400t^{3} + 13381632t^{2} - 3981312t - 1105920\] \[B(t) = -7344t^{18} - 93312t^{17} - 554688t^{16} - 1244160t^{15} + 12856320t^{14} + 90574848t^{13} + 98316288t^{12} - 258785280t^{11} - 80289792t^{10} - 321159168t^{8} + 4140564480t^{7} + 6292242432t^{6} - 23187161088t^{5} + 13164871680t^{4} + 5096079360t^{3} - 9088008192t^{2} + 6115295232t - 1925185536\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - x^2 - 13x + 85$, with conductor $768$
Generic density of odd order reductions $417/1792$

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