Invariants
| Base field: | $\F_{19}$ |
| Dimension: | $2$ |
| L-polynomial: | $1 - 4 x + 32 x^{2} - 76 x^{3} + 361 x^{4}$ |
| Frobenius angles: | $\pm0.298277766669$, $\pm0.542564572634$ |
| Angle rank: | $2$ (numerical) |
| Number field: | 4.0.5894400.1 |
| Galois group: | $D_{4}$ |
| Jacobians: | $12$ |
This isogeny class is simple and geometrically simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.
Newton polygon
This isogeny class is ordinary.
| $p$-rank: | $2$ |
| Slopes: | $[0, 0, 1, 1]$ |
Point counts
Point counts of the abelian variety
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
|---|---|---|---|---|---|
| $A(\F_{q^r})$ | $314$ | $148836$ | $47680586$ | $16979806224$ | $6136112715674$ |
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
|---|---|---|---|---|---|---|---|---|---|---|
| $C(\F_{q^r})$ | $16$ | $410$ | $6952$ | $130294$ | $2478136$ | $47044586$ | $893766064$ | $16983346654$ | $322689380368$ | $6131072349050$ |
Jacobians and polarizations
This isogeny class is principally polarizable and contains the Jacobians of 12 curves (of which all are hyperelliptic):
- $y^2=4 x^6+11 x^4+15 x^3+7 x^2+10 x+11$
- $y^2=4 x^6+14 x^5+9 x^4+8 x^3+18 x^2+15 x+8$
- $y^2=11 x^6+15 x^5+17 x^4+14 x^3+5 x^2+3 x+16$
- $y^2=6 x^6+5 x^4+10 x^3+18 x^2+2 x+2$
- $y^2=17 x^6+x^5+8 x^4+7 x^3+15 x^2+7 x+17$
- $y^2=18 x^6+8 x^5+x^4+16 x^3+15 x^2+18 x+12$
- $y^2=5 x^6+15 x^5+8 x^4+14 x^3+10 x^2+17 x+9$
- $y^2=3 x^6+11 x^5+15 x^4+17 x^3+x^2+12 x+15$
- $y^2=2 x^6+3 x^5+12 x^4+12 x^3+2 x^2+7 x+10$
- $y^2=5 x^6+17 x^5+9 x^4+4 x^3+12 x^2+11 x+1$
- $y^2=9 x^6+5 x^5+16 x^4+18 x^3+3 x^2+5 x$
- $y^2=13 x^6+17 x^5+13 x^4+x^3+9 x^2+5 x+1$
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{19}$.
Endomorphism algebra over $\F_{19}$| The endomorphism algebra of this simple isogeny class is 4.0.5894400.1. |
Base change
This is a primitive isogeny class.
Twists
Below is a list of all twists of this isogeny class.
| Twist | Extension degree | Common base change |
|---|---|---|
| 2.19.e_bg | $2$ | (not in LMFDB) |