The modular curve $X_{231}$

Curve name $X_{231}$
Index $48$
Level $16$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 1 & 1 \\ 12 & 15 \end{matrix}\right], \left[ \begin{matrix} 3 & 6 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 0 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 0 \\ 12 & 15 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $12$ $X_{27}$
$8$ $24$ $X_{94}$
Meaning/Special name
Chosen covering $X_{94}$
Curves that $X_{231}$ minimally covers $X_{94}$, $X_{110}$, $X_{112}$
Curves that minimally cover $X_{231}$ $X_{231a}$, $X_{231b}$, $X_{231c}$, $X_{231d}$
Curves that minimally cover $X_{231}$ and have infinitely many rational points. $X_{231a}$, $X_{231b}$, $X_{231c}$, $X_{231d}$
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{231}) = \mathbb{Q}(f_{231}), f_{94} = \frac{8f_{231} + 8}{f_{231}^{2} - 2}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 + 24009700x + 65021152000$, with conductor $421600$
Generic density of odd order reductions $9249/57344$

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