The modular curve $X_{204b}$

Curve name $X_{204b}$
Index $96$
Level $8$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 7 & 6 \\ 4 & 5 \end{matrix}\right], \left[ \begin{matrix} 1 & 0 \\ 4 & 7 \end{matrix}\right], \left[ \begin{matrix} 3 & 6 \\ 4 & 7 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $6$ $X_{8}$
$4$ $24$ $X_{25i}$
Meaning/Special name
Chosen covering $X_{204}$
Curves that $X_{204b}$ minimally covers
Curves that minimally cover $X_{204b}$
Curves that minimally cover $X_{204b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -7884t^{16} - 100224t^{15} - 680832t^{14} - 2225664t^{13} - 7402752t^{12} - 13547520t^{11} - 14321664t^{10} - 24993792t^{9} - 74041344t^{8} + 99975168t^{7} - 229146624t^{6} + 867041280t^{5} - 1895104512t^{4} + 2279079936t^{3} - 2788687872t^{2} + 1642070016t - 516685824\] \[B(t) = -257040t^{24} - 5453568t^{23} - 48418560t^{22} - 308689920t^{21} - 1344397824t^{20} - 4317401088t^{19} - 11010650112t^{18} - 27196342272t^{17} - 40513499136t^{16} - 66762178560t^{15} - 51969392640t^{14} - 34780741632t^{13} - 401266704384t^{12} + 139122966528t^{11} - 831510282240t^{10} + 4272779427840t^{9} - 10371455778816t^{8} + 27849054486528t^{7} - 45099622858752t^{6} + 70736299425792t^{5} - 88106455793664t^{4} + 80921210388480t^{3} - 50770539970560t^{2} + 22873922076672t - 4312415600640\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 + x^2 - 97x - 385$, with conductor $192$
Generic density of odd order reductions $271/2688$

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