The modular curve $X_{221b}$

Curve name $X_{221b}$
Index $96$
Level $16$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 15 & 14 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 9 & 9 \\ 12 & 3 \end{matrix}\right], \left[ \begin{matrix} 7 & 14 \\ 12 & 3 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $24$ $X_{27f}$
$8$ $48$ $X_{95b}$
Meaning/Special name
Chosen covering $X_{221}$
Curves that $X_{221b}$ minimally covers
Curves that minimally cover $X_{221b}$
Curves that minimally cover $X_{221b}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -108t^{16} + 24192t^{8} - 27648\] \[B(t) = 432t^{24} + 228096t^{16} - 3649536t^{8} - 1769472\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 44x - 7120$, with conductor $1088$
Generic density of odd order reductions $13411/86016$

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