The modular curve $X_{231d}$

Curve name $X_{231d}$
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 & 6 \\ 0 & 3 \end{matrix}\right], \left[ \begin{matrix} 3 & 3 \\ 0 & 13 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $3$ $X_{6}$
$4$ $24$ $X_{27f}$
$8$ $48$ $X_{94b}$
Meaning/Special name
Chosen covering $X_{231}$
Curves that $X_{231d}$ minimally covers
Curves that minimally cover $X_{231d}$
Curves that minimally cover $X_{231d}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = 81t^{32} + 2592t^{31} + 29376t^{30} + 77760t^{29} - 1260576t^{28} - 12845952t^{27} - 36336384t^{26} + 138108672t^{25} + 1395223488t^{24} + 3825695232t^{23} - 2768200704t^{22} - 50173350912t^{21} - 150280220160t^{20} - 145445787648t^{19} + 379652935680t^{18} + 1708861501440t^{17} + 3220399351296t^{16} + 3417723002880t^{15} + 1518611742720t^{14} - 1163566301184t^{13} - 2404483522560t^{12} - 1605547229184t^{11} - 177164845056t^{10} + 489688989696t^{9} + 357177212928t^{8} + 70711640064t^{7} - 37208457216t^{6} - 26308509696t^{5} - 5163319296t^{4} + 637009920t^{3} + 481296384t^{2} + 84934656t + 5308416\] \[B(t) = 3888t^{47} + 182736t^{46} + 3659040t^{45} + 38568960t^{44} + 187811136t^{43} - 344399040t^{42} - 10800065664t^{41} - 60940615680t^{40} - 48629687040t^{39} + 1245342428928t^{38} + 7189108452864t^{37} + 10251054268416t^{36} - 70032466916352t^{35} - 428112906716160t^{34} - 815251264763904t^{33} + 1529004209209344t^{32} + 13197677010739200t^{31} + 33634427462295552t^{30} + 19212936944762880t^{29} - 147683421237805056t^{28} - 579319473820631040t^{27} - 1127610012248801280t^{26} - 1181341148239429632t^{25} + 2362682296478859264t^{23} + 4510440048995205120t^{22} + 4634555790565048320t^{21} + 2362934739804880896t^{20} - 614813982232412160t^{19} - 2152603357586915328t^{18} - 1689302657374617600t^{17} - 391425077557592064t^{16} + 417408647559118848t^{15} + 438387616477347840t^{14} + 143426492244688896t^{13} - 41988318283431936t^{12} - 58893176445861888t^{11} - 20403690355556352t^{10} + 1593497584926720t^{9} + 3993804189204480t^{8} + 1415586206711808t^{7} + 90282141941760t^{6} - 98467124871168t^{5} - 40442485800960t^{4} - 7673563054080t^{3} - 766450335744t^{2} - 32614907904t\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 15527434426559x - 23572637476693292960$, with conductor $47524672$
Generic density of odd order reductions $13411/86016$

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