The modular curve $X_{211r}$

Curve name $X_{211r}$
Index $96$
Level $16$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 9 & 0 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 5 & 5 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 15 & 0 \\ 8 & 1 \end{matrix}\right], \left[ \begin{matrix} 11 & 11 \\ 0 & 3 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $6$ $X_{13}$
$8$ $48$ $X_{85n}$
Meaning/Special name
Chosen covering $X_{211}$
Curves that $X_{211r}$ minimally covers
Curves that minimally cover $X_{211r}$
Curves that minimally cover $X_{211r}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -27t^{22} - 12960t^{21} - 232200t^{20} - 984960t^{19} - 116208t^{18} + 9953280t^{17} + 17459712t^{16} - 6635520t^{15} - 26445312t^{14} - 245514240t^{13} - 213331968t^{12} + 982056960t^{11} - 423124992t^{10} + 424673280t^{9} + 4469686272t^{8} - 10192158720t^{7} - 475987968t^{6} + 16137584640t^{5} - 15217459200t^{4} + 3397386240t^{3} - 28311552t^{2}\] \[B(t) = -54t^{33} + 54432t^{32} + 3595752t^{31} + 50077440t^{30} + 273396384t^{29} + 232533504t^{28} - 2892509568t^{27} - 10046840832t^{26} - 6398258688t^{25} + 45830873088t^{24} + 149344487424t^{23} + 71010680832t^{22} - 185424076800t^{21} - 793045499904t^{20} - 3462698336256t^{19} + 2461406330880t^{18} + 13850793345024t^{17} - 12688727998464t^{16} + 11867140915200t^{15} + 18178734292992t^{14} - 152928755122176t^{13} + 187723256168448t^{12} + 104829070344192t^{11} - 658429760765952t^{10} + 758254028193792t^{9} + 243829051490304t^{8} - 1146707546996736t^{7} + 840160027607040t^{6} - 241306831945728t^{5} + 14611478740992t^{4} + 57982058496t^{3}\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 + xy = x^3 - x^2 - 17287200x + 27669604050$, with conductor $630$
Generic density of odd order reductions $271/2688$

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