The modular curve $X_{205b}$

Curve name $X_{205b}$
Index $96$
Level $16$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 1 & 2 \\ 0 & 1 \end{matrix}\right], \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]$
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 $X_{205b}$ minimally covers
Curves that minimally cover $X_{205b}$
Curves that minimally cover $X_{205b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -108t^{24} + 6264t^{20} - 1620t^{16} - 15984t^{12} - 1620t^{8} + 6264t^{4} - 108\] \[B(t) = 432t^{36} + 55728t^{32} - 285120t^{28} - 423360t^{24} + 541728t^{20} + 541728t^{16} - 423360t^{12} - 285120t^{8} + 55728t^{4} + 432\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - x^2 + 56597375x + 255124305025$, with conductor $277440$
Generic density of odd order reductions $5/42$

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