## The modular curve $X_{531}$

Curve name $X_{531}$
Index $96$
Level $32$
Genus $2$
Does the subgroup contain $-I$? Yes
Generating matrices $\left[ \begin{matrix} 11 & 0 \\ 24 & 7 \end{matrix}\right], \left[ \begin{matrix} 7 & 7 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 9 & 18 \\ 0 & 1 \end{matrix}\right], \left[ \begin{matrix} 13 & 0 \\ 8 & 5 \end{matrix}\right], \left[ \begin{matrix} 15 & 0 \\ 0 & 7 \end{matrix}\right]$
Images in lower levels
 Level Index of image Corresponding curve $2$ $3$ $X_{6}$ $4$ $12$ $X_{27}$ $8$ $24$ $X_{92}$ $16$ $48$ $X_{207}$
Meaning/Special name
Chosen covering $X_{207}$
Curves that $X_{531}$ minimally covers $X_{207}$
Curves that minimally cover $X_{531}$
Curves that minimally cover $X_{531}$ and have infinitely many rational points.
Model $y^2 + (x^3 + x^2 + x + 1)y = -x^5 - x^4 - x^3 - x^2$
 Rational point Image on the $j$-line $(1 : -1 : 0)$ $\infty$ $(1 : 0 : 0)$ $\infty$ $(-1 : 0 : 1)$ $\infty$ $(0 : -1 : 1)$ $\infty$ $(0 : 0 : 1)$ $\infty$ $(1 : -2 : 1)$ $\infty$
Elliptic curve whose $2$-adic image is the subgroup None