The modular curve $X_{205}$

Curve name $X_{205}$
Index $48$
Level $8$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 0 & 7 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 1 \\ 0 & 1 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $12$ $X_{27}$
Meaning/Special name
Chosen covering $X_{85}$
Curves that $X_{205}$ minimally covers $X_{85}$, $X_{86}$, $X_{92}$
Curves that minimally cover $X_{205}$ $X_{444}$, $X_{453}$, $X_{476}$, $X_{478}$, $X_{205a}$, $X_{205b}$, $X_{205c}$, $X_{205d}$, $X_{205e}$, $X_{205f}$, $X_{205g}$, $X_{205h}$, $X_{205i}$, $X_{205j}$, $X_{205k}$, $X_{205l}$
Curves that minimally cover $X_{205}$ and have infinitely many rational points. $X_{205a}$, $X_{205b}$, $X_{205c}$, $X_{205d}$, $X_{205e}$, $X_{205f}$, $X_{205g}$, $X_{205h}$, $X_{205i}$, $X_{205j}$, $X_{205k}$, $X_{205l}$
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{205}) = \mathbb{Q}(f_{205}), f_{85} = \frac{f_{205}^{2} + 1}{f_{205}}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 - x^2 + 27540x - 2745500$, with conductor $1530$
Generic density of odd order reductions $25/224$

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