The modular curve $X_{85}$

Curve name $X_{85}$
Index $24$
Level $8$
Genus $0$
Does the subgroup contain $-I$? Yes
Generating matrices $ \left[ \begin{matrix} 3 & 3 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 0 & 7 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 0 & 3 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $6$ $X_{13}$
Meaning/Special name
Chosen covering $X_{36}$
Curves that $X_{85}$ minimally covers $X_{36}$
Curves that minimally cover $X_{85}$ $X_{192}$, $X_{199}$, $X_{202}$, $X_{205}$, $X_{211}$, $X_{219}$, $X_{225}$, $X_{236}$, $X_{335}$, $X_{339}$, $X_{341}$, $X_{344}$, $X_{85a}$, $X_{85b}$, $X_{85c}$, $X_{85d}$, $X_{85e}$, $X_{85f}$, $X_{85g}$, $X_{85h}$, $X_{85i}$, $X_{85j}$, $X_{85k}$, $X_{85l}$, $X_{85m}$, $X_{85n}$, $X_{85o}$, $X_{85p}$
Curves that minimally cover $X_{85}$ and have infinitely many rational points. $X_{192}$, $X_{199}$, $X_{202}$, $X_{205}$, $X_{211}$, $X_{219}$, $X_{225}$, $X_{236}$, $X_{85a}$, $X_{85b}$, $X_{85c}$, $X_{85d}$, $X_{85e}$, $X_{85f}$, $X_{85g}$, $X_{85h}$, $X_{85i}$, $X_{85j}$, $X_{85k}$, $X_{85l}$, $X_{85m}$, $X_{85n}$, $X_{85o}$, $X_{85p}$
Model \[\mathbb{P}^{1}, \mathbb{Q}(X_{85}) = \mathbb{Q}(f_{85}), f_{36} = \frac{8}{f_{85}^{2} - 2}\]
Info about rational points None
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 + x^2 - 850x - 27125$, with conductor $525$
Generic density of odd order reductions $19/168$

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