Properties

Label 228.240.17.b.1
Level $228$
Index $240$
Genus $17$
Cusps $8$
$\Q$-cusps $4$

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Invariants

Level: $228$ $\SL_2$-level: $76$ Newform level: $1$
Index: $240$ $\PSL_2$-index:$240$
Genus: $17 = 1 + \frac{ 240 }{12} - \frac{ 0 }{4} - \frac{ 0 }{3} - \frac{ 8 }{2}$
Cusps: $8$ (of which $4$ are rational) Cusp widths $2^{2}\cdot4^{2}\cdot38^{2}\cdot76^{2}$ Cusp orbits $1^{4}\cdot2^{2}$
Elliptic points: $0$ of order $2$ and $0$ of order $3$
Analytic rank: not computed
$\Q$-gonality: $4 \le \gamma \le 17$
$\overline{\Q}$-gonality: $4 \le \gamma \le 17$
Rational cusps: $4$
Rational CM points: none

Other labels

Cummins and Pauli (CP) label: 76A17

Level structure

$\GL_2(\Z/228\Z)$-generators: $\begin{bmatrix}49&152\\2&155\end{bmatrix}$, $\begin{bmatrix}107&190\\126&145\end{bmatrix}$, $\begin{bmatrix}111&38\\92&155\end{bmatrix}$, $\begin{bmatrix}115&152\\12&79\end{bmatrix}$, $\begin{bmatrix}189&190\\220&161\end{bmatrix}$, $\begin{bmatrix}215&38\\186&223\end{bmatrix}$
Contains $-I$: yes
Quadratic refinements: 228.480.17-228.b.1.1, 228.480.17-228.b.1.2, 228.480.17-228.b.1.3, 228.480.17-228.b.1.4, 228.480.17-228.b.1.5, 228.480.17-228.b.1.6, 228.480.17-228.b.1.7, 228.480.17-228.b.1.8, 228.480.17-228.b.1.9, 228.480.17-228.b.1.10, 228.480.17-228.b.1.11, 228.480.17-228.b.1.12, 228.480.17-228.b.1.13, 228.480.17-228.b.1.14, 228.480.17-228.b.1.15, 228.480.17-228.b.1.16, 228.480.17-228.b.1.17, 228.480.17-228.b.1.18, 228.480.17-228.b.1.19, 228.480.17-228.b.1.20
Cyclic 228-isogeny field degree: $8$
Cyclic 228-torsion field degree: $576$
Full 228-torsion field degree: $2363904$

Rational points

This modular curve has 4 rational cusps but no known non-cuspidal rational points.

Modular covers

The following modular covers realize this modular curve as a fiber product over $X(1)$.

Factor curve Level Index Degree Genus Rank
12.12.0.b.1 $12$ $20$ $20$ $0$ $0$
$X_0(19)$ $19$ $12$ $12$ $1$ $0$

This modular curve minimally covers the modular curves listed below.

Covered curve Level Index Degree Genus Rank
12.12.0.b.1 $12$ $20$ $20$ $0$ $0$
38.120.8.a.1 $38$ $2$ $2$ $8$ $0$
228.120.8.c.1 $228$ $2$ $2$ $8$ $?$
228.120.9.e.1 $228$ $2$ $2$ $9$ $?$