The modular curve $X_{205a}$

Curve name $X_{205a}$
Index $96$
Level $16$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 7 & 0 \\ 8 & 7 \end{matrix}\right], \left[ \begin{matrix} 7 & 0 \\ 8 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 9 \\ 8 & 1 \end{matrix}\right], \left[ \begin{matrix} 1 & 2 \\ 8 & 1 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $12$ $X_{27}$
$8$ $48$ $X_{205}$
Meaning/Special name
Chosen covering $X_{205}$
Curves that $X_{205a}$ minimally covers
Curves that minimally cover $X_{205a}$
Curves that minimally cover $X_{205a}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -108t^{32} + 6480t^{28} - 14256t^{24} - 6480t^{20} + 28728t^{16} - 6480t^{12} - 14256t^{8} + 6480t^{4} - 108\] \[B(t) = 432t^{48} + 54432t^{44} - 451008t^{40} + 598752t^{36} + 900720t^{32} - 2068416t^{28} + 2068416t^{20} - 900720t^{16} - 598752t^{12} + 451008t^{8} - 54432t^{4} - 432\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 + x^2 - 658532625x - 105614604984375$, with conductor $252150$
Generic density of odd order reductions $51/448$

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