The modular curve $X_{220}$

Curve name $X_{220}$
Index $48$
Level $16$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 1 & 3 \\ 12 & 15 \end{matrix}\right], \left[ \begin{matrix} 1 & 0 \\ 10 & 15 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $6$ $X_{11}$
$8$ $24$ $X_{81}$
Meaning/Special name
Chosen covering $X_{81}$
Curves that $X_{220}$ minimally covers $X_{81}$, $X_{109}$, $X_{112}$
Curves that minimally cover $X_{220}$
Curves that minimally cover $X_{220}$ and have infinitely many rational points.
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{220}) = \mathbb{Q}(f_{220}), f_{81} = \frac{f_{220}^{2} + 2f_{220} - 1}{f_{220}^{2} + 1}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 770x + 8224$, with conductor $4352$
Generic density of odd order reductions $45667/172032$

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