Invariants
Level: | $42$ | $\SL_2$-level: | $14$ | ||||
Index: | $32$ | $\PSL_2$-index: | $16$ | ||||
Genus: | $0 = 1 + \frac{ 16 }{12} - \frac{ 0 }{4} - \frac{ 4 }{3} - \frac{ 2 }{2}$ | ||||||
Cusps: | $2$ (all of which are rational) | Cusp widths | $2\cdot14$ | Cusp orbits | $1^{2}$ | ||
Elliptic points: | $0$ of order $2$ and $4$ of order $3$ | ||||||
$\Q$-gonality: | $1$ | ||||||
$\overline{\Q}$-gonality: | $1$ | ||||||
Rational cusps: | $2$ | ||||||
Rational CM points: | yes $\quad(D =$ $-7$) |
Other labels
Cummins and Pauli (CP) label: | 14B0 |
Rouse, Sutherland, and Zureick-Brown (RSZB) label: | 42.32.0.12 |
Level structure
$\GL_2(\Z/42\Z)$-generators: | $\begin{bmatrix}3&25\\37&8\end{bmatrix}$, $\begin{bmatrix}15&16\\19&27\end{bmatrix}$ |
Contains $-I$: | no $\quad$ (see 14.16.0.b.1 for the level structure with $-I$) |
Cyclic 42-isogeny field degree: | $12$ |
Cyclic 42-torsion field degree: | $144$ |
Full 42-torsion field degree: | $18144$ |
Models
This modular curve is isomorphic to $\mathbb{P}^1$.
Rational points
This modular curve has infinitely many rational points, including 3 stored non-cuspidal points.
Maps to other modular curves
$j$-invariant map of degree 16 to the modular curve $X(1)$ :
$\displaystyle j$ | $=$ | $\displaystyle -\frac{1}{2^{14}\cdot3^{14}}\cdot\frac{x^{16}(7x^{2}-42xy+36y^{2})^{3}(7x^{2}+42xy+36y^{2})^{3}(7x^{4}-468x^{2}y^{2}+9072y^{4})}{y^{14}x^{18}}$ |
Modular covers
This modular curve minimally covers the modular curves listed below.
Covered curve | Level | Index | Degree | Genus | Rank |
---|---|---|---|---|---|
21.16.0-7.a.1.1 | $21$ | $2$ | $2$ | $0$ | $0$ |
42.16.0-7.a.1.2 | $42$ | $2$ | $2$ | $0$ | $0$ |
This modular curve is minimally covered by the modular curves in the database listed below.
Covering curve | Level | Index | Degree | Genus |
---|---|---|---|---|
42.96.2-14.e.1.2 | $42$ | $3$ | $3$ | $2$ |
42.96.2-14.e.2.1 | $42$ | $3$ | $3$ | $2$ |
42.96.2-14.f.1.1 | $42$ | $3$ | $3$ | $2$ |
42.96.2-14.g.1.1 | $42$ | $3$ | $3$ | $2$ |
42.96.4-42.c.1.6 | $42$ | $3$ | $3$ | $4$ |
42.128.3-42.c.1.6 | $42$ | $4$ | $4$ | $3$ |
42.224.5-14.c.1.1 | $42$ | $7$ | $7$ | $5$ |
84.128.3-28.c.1.4 | $84$ | $4$ | $4$ | $3$ |
126.96.2-126.j.1.3 | $126$ | $3$ | $3$ | $2$ |
126.96.2-126.j.2.1 | $126$ | $3$ | $3$ | $2$ |
126.96.2-126.k.1.4 | $126$ | $3$ | $3$ | $2$ |
126.96.2-126.k.2.2 | $126$ | $3$ | $3$ | $2$ |
126.96.2-126.n.1.3 | $126$ | $3$ | $3$ | $2$ |
126.96.2-126.n.2.1 | $126$ | $3$ | $3$ | $2$ |
210.160.4-70.c.1.3 | $210$ | $5$ | $5$ | $4$ |
210.192.7-70.c.1.1 | $210$ | $6$ | $6$ | $7$ |
210.320.11-70.c.1.4 | $210$ | $10$ | $10$ | $11$ |
294.224.5-98.b.1.2 | $294$ | $7$ | $7$ | $5$ |