Invariants
| Base field: | $\F_{13}$ |
| Dimension: | $2$ |
| L-polynomial: | $( 1 - 2 x + 13 x^{2} )^{2}$ |
| $1 - 4 x + 30 x^{2} - 52 x^{3} + 169 x^{4}$ | |
| Frobenius angles: | $\pm0.410543812489$, $\pm0.410543812489$ |
| Angle rank: | $1$ (numerical) |
| Jacobians: | $8$ |
| Cyclic group of points: | no |
| Non-cyclic primes: | $2, 3$ |
This isogeny class is not 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
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
|---|---|---|---|---|---|
| $A(\F_{q^r})$ | $144$ | $36864$ | $5143824$ | $807469056$ | $136968088464$ |
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
|---|---|---|---|---|---|---|---|---|---|---|
| $C(\F_{q^r})$ | $10$ | $214$ | $2338$ | $28270$ | $368890$ | $4825798$ | $62777746$ | $815802334$ | $10604262634$ | $137857087414$ |
Jacobians and polarizations
This isogeny class is principally polarizable and contains the Jacobians of 8 curves (of which all are hyperelliptic):
- $y^2=6 x^6+6 x^5+9 x^4+8 x^3+9 x^2+6 x+6$
- $y^2=6 x^6+3 x^5+5 x^4+8 x^3+11 x^2+x+7$
- $y^2=x^6+12$
- $y^2=4 x^6+x^4+x^2+4$
- $y^2=11 x^6+7 x^5+12 x^4+10 x^3+12 x^2+7 x+11$
- $y^2=7 x^6+7 x^4+7 x^2+7$
- $y^2=2 x^6+10 x^5+5 x^4+9 x^3+5 x^2+10 x+2$
- $y^2=x^6+3 x^3+1$
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{13}$.
Endomorphism algebra over $\F_{13}$| The isogeny class factors as 1.13.ac 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-3}) \)$)$ |
Base change
This is a primitive isogeny class.