The modular curve $X_{87b}$

Curve name $X_{87b}$
Index $48$
Level $8$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 4 & 1 \end{matrix}\right], \left[ \begin{matrix} 7 & 6 \\ 4 & 3 \end{matrix}\right], \left[ \begin{matrix} 1 & 0 \\ 0 & 7 \end{matrix}\right], \left[ \begin{matrix} 5 & 2 \\ 0 & 1 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $6$ $X_{8}$
$4$ $12$ $X_{25}$
Meaning/Special name
Chosen covering $X_{87}$
Curves that $X_{87b}$ minimally covers
Curves that minimally cover $X_{87b}$
Curves that minimally cover $X_{87b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -6912t^{16} - 34560t^{14} - 72576t^{12} - 82944t^{10} - 56160t^{8} - 23328t^{6} - 6156t^{4} - 1080t^{2} - 108\] \[B(t) = -221184t^{24} - 1658880t^{22} - 5557248t^{20} - 10962432t^{18} - 14100480t^{16} - 12317184t^{14} - 7318080t^{12} - 2822688t^{10} - 593568t^{8} - 5616t^{6} + 29808t^{4} + 6480t^{2} + 432\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 4575x - 22750$, with conductor $1800$
Generic density of odd order reductions $691/5376$

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