The modular curve $X_{231c}$

Curve name $X_{231c}$
Index $96$
Level $16$
Genus $0$
Does the subgroup contain $-I$? No
Generating matrices $ \left[ \begin{matrix} 3 & 3 \\ 4 & 13 \end{matrix}\right], \left[ \begin{matrix} 3 & 3 \\ 0 & 13 \end{matrix}\right], \left[ \begin{matrix} 3 & 9 \\ 4 & 5 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $24$ $X_{27h}$
$8$ $48$ $X_{94d}$
Meaning/Special name
Chosen covering $X_{231}$
Curves that $X_{231c}$ minimally covers
Curves that minimally cover $X_{231c}$
Curves that minimally cover $X_{231c}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = 324t^{16} + 5184t^{15} + 13824t^{14} - 169344t^{13} - 1294272t^{12} - 2951424t^{11} + 1935360t^{10} + 23459328t^{9} + 50239872t^{8} + 46918656t^{7} + 7741440t^{6} - 23611392t^{5} - 20708352t^{4} - 5419008t^{3} + 884736t^{2} + 663552t + 82944\] \[B(t) = 31104t^{23} + 715392t^{22} + 6130944t^{21} + 18579456t^{20} - 53125632t^{19} - 571802112t^{18} - 1321712640t^{17} + 2526806016t^{16} + 22755962880t^{15} + 60751171584t^{14} + 74833403904t^{13} - 149666807808t^{11} - 243004686336t^{10} - 182047703040t^{9} - 40428896256t^{8} + 42294804480t^{7} + 36595335168t^{6} + 6800080896t^{5} - 4756340736t^{4} - 3139043328t^{3} - 732561408t^{2} - 63700992t\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 + 960388x + 520169216$, with conductor $84320$
Generic density of odd order reductions $9827/86016$

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