The modular curve $X_{216}$

Curve name $X_{216}$
Index $48$
Level $16$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 10 & 15 \end{matrix}\right], \left[ \begin{matrix} 1 & 2 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 1 & 1 \\ 10 & 15 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $6$ $X_{11}$
$8$ $24$ $X_{77}$
Meaning/Special name
Chosen covering $X_{77}$
Curves that $X_{216}$ minimally covers $X_{77}$, $X_{110}$, $X_{112}$
Curves that minimally cover $X_{216}$ $X_{520}$, $X_{533}$
Curves that minimally cover $X_{216}$ and have infinitely many rational points.
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{216}) = \mathbb{Q}(f_{216}), f_{77} = \frac{f_{216}^{2} - \frac{1}{8}}{f_{216}}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - x^2 - 14413x + 1182613$, with conductor $13056$
Generic density of odd order reductions $12833/57344$

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