The modular curve $X_{191}$

Curve name $X_{191}$
Index $48$
Level $8$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 5 & 0 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 7 & 7 \\ 2 & 1 \end{matrix}\right], \left[ \begin{matrix} 3 & 3 \\ 0 & 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 $X_{64}$
Curves that $X_{191}$ minimally covers $X_{64}$
Curves that minimally cover $X_{191}$ $X_{443}$, $X_{445}$, $X_{447}$, $X_{461}$
Curves that minimally cover $X_{191}$ and have infinitely many rational points.
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{191}) = \mathbb{Q}(f_{191}), f_{64} = \frac{\frac{1}{2}f_{191}^{2} + 4}{f_{191}^{2} + 8f_{191} + 8}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 + x^2 + 122x - 10940$, with conductor $294$
Generic density of odd order reductions $269/1344$

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