The modular curve $X_{204a}$

Curve name $X_{204a}$
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} 5 & 2 \\ 0 & 7 \end{matrix}\right], \left[ \begin{matrix} 3 & 6 \\ 4 & 7 \end{matrix}\right]$
Images in lower levels
LevelIndex of imageCorresponding curve
$2$ $6$ $X_{8}$
$4$ $12$ $X_{25}$
Meaning/Special name
Chosen covering $X_{204}$
Curves that $X_{204a}$ minimally covers
Curves that minimally cover $X_{204a}$
Curves that minimally cover $X_{204a}$ and have infinitely many rational points.
Model $\mathbb{P}^{1}$, a universal elliptic curve over an appropriate base is given by \[y^2 = x^3 + A(t)x + B(t), \text{ where}\] \[A(t) = -17739t^{24} - 320112t^{23} - 3144528t^{22} - 18767808t^{21} - 84271968t^{20} - 275035392t^{19} - 733798656t^{18} - 1430369280t^{17} - 2579662080t^{16} - 3808124928t^{15} - 7866851328t^{14} - 5472092160t^{13} - 8468250624t^{12} + 21888368640t^{11} - 125869621248t^{10} + 243719995392t^{9} - 660393492480t^{8} + 1464698142720t^{7} - 3005639294976t^{6} + 4506179862528t^{5} - 5522847694848t^{4} + 4919868260352t^{3} - 3297276592128t^{2} + 1342647042048t - 297611034624\] \[B(t) = 867510t^{36} + 25345872t^{35} + 349986096t^{34} + 3283257024t^{33} + 22604196960t^{32} + 121327994880t^{31} + 519456098304t^{30} + 1836846637056t^{29} + 5448260745216t^{28} + 14046538088448t^{27} + 31155737149440t^{26} + 61732891459584t^{25} + 103622008209408t^{24} + 177813547646976t^{23} + 273955331506176t^{22} + 509882161692672t^{21} + 580576552943616t^{20} + 510617469321216t^{19} + 787850868031488t^{18} - 2042469877284864t^{17} + 9289224847097856t^{16} - 32632458348331008t^{15} + 70132564865581056t^{14} - 182081072790503424t^{13} + 424435745625735168t^{12} - 1011431693673824256t^{11} + 2041822389825699840t^{10} - 3682215680658112512t^{9} + 5712915459175612416t^{8} - 7704293197190529024t^{7} + 8715027163763441664t^{6} - 8142183907794616320t^{5} + 6067767918471413760t^{4} - 3525370385610571776t^{3} + 1503178836374716416t^{2} - 435438765314408448t + 59614833263247360\]
Info about rational points
Comments on finding rational points None
Elliptic curve whose $2$-adic image is the subgroup $y^2 = x^3 - 219x + 1190$, with conductor $72$
Generic density of odd order reductions $299/2688$

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