The modular curve $X_{209}$

Curve name $X_{209}$
Index $48$
Level $16$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 14 & 5 \end{matrix}\right], \left[ \begin{matrix} 1 & 0 \\ 0 & 5 \end{matrix}\right], \left[ \begin{matrix} 3 & 6 \\ 10 & 5 \end{matrix}\right], \left[ \begin{matrix} 3 & 0 \\ 0 & 3 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $6$ $X_{8}$
$4$ $12$ $X_{24}$
$8$ $24$ $X_{61}$
Meaning/Special name
Chosen covering $X_{61}$
Curves that $X_{209}$ minimally covers $X_{61}$, $X_{109}$, $X_{110}$
Curves that minimally cover $X_{209}$ $X_{209a}$, $X_{209b}$, $X_{209c}$, $X_{209d}$
Curves that minimally cover $X_{209}$ and have infinitely many rational points. $X_{209a}$, $X_{209b}$, $X_{209c}$, $X_{209d}$
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{209}) = \mathbb{Q}(f_{209}), f_{61} = -f_{209}^{2}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 - x^2 - 12336x + 530432$, with conductor $4626$
Generic density of odd order reductions $9249/57344$

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