Properties

Label 2.17.a_ac
Base field $\F_{17}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{17}$
Dimension:  $2$
L-polynomial:  $( 1 - 6 x + 17 x^{2} )( 1 + 6 x + 17 x^{2} )$
  $1 - 2 x^{2} + 289 x^{4}$
Frobenius angles:  $\pm0.240632536990$, $\pm0.759367463010$
Angle rank:  $1$ (numerical)
Jacobians:  $49$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $288$ $82944$ $24139296$ $7072137216$ $2015993076768$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $18$ $286$ $4914$ $84670$ $1419858$ $24141022$ $410338674$ $6975432574$ $118587876498$ $2015992253086$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 49 curves (of which all are hyperelliptic):

  • $y^2=15 x^6+9 x^5+14 x^4+x^3+x^2+x+7$
  • $y^2=11 x^6+16 x^4+16 x^3+15 x^2+3 x+12$
  • $y^2=16 x^6+14 x^4+14 x^3+11 x^2+9 x+2$
  • $y^2=4 x^6+3 x^4+15 x^3+3 x^2+10 x$
  • $y^2=12 x^6+9 x^4+11 x^3+9 x^2+13 x$
  • $y^2=2 x^6+16 x^5+5 x^4+11 x^2+16 x+9$
  • $y^2=x^6+3 x^5+6 x^4+7 x^3+15 x^2+11 x+15$
  • $y^2=3 x^6+10 x^5+x^4+12 x^3+7 x^2+5 x+16$
  • $y^2=x^6+6 x^5+7 x^4+16 x^3+13 x^2+7 x+11$
  • $y^2=3 x^6+x^5+4 x^4+14 x^3+5 x^2+4 x+16$
  • $y^2=x^6+9 x^5+x^4+6 x^3+15 x^2+10 x+2$
  • $y^2=3 x^6+10 x^5+3 x^4+x^3+11 x^2+13 x+6$
  • $y^2=4 x^5+7 x^4+7 x^3+x^2+15 x$
  • $y^2=6 x^6+12 x^5+2 x^4+16 x^3+x^2+10 x+12$
  • $y^2=x^6+2 x^5+6 x^4+14 x^3+3 x^2+13 x+2$
  • $y^2=x^6+5 x^5+12 x^4+14 x^3+13 x^2+9 x+3$
  • $y^2=10 x^6+12 x^5+2 x^4+3 x^3+6 x^2+4 x+10$
  • $y^2=13 x^6+2 x^5+6 x^4+9 x^3+x^2+12 x+13$
  • $y^2=16 x^6+4 x^5+9 x^4+6 x^3+4 x^2+15 x+9$
  • $y^2=14 x^6+12 x^5+10 x^4+x^3+12 x^2+11 x+10$
  • and 29 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{17^{2}}$.

Endomorphism algebra over $\F_{17}$
The isogeny class factors as 1.17.ag $\times$ 1.17.g and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{17}$
The base change of $A$ to $\F_{17^{2}}$ is 1.289.ac 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-2}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.17.am_cs$2$(not in LMFDB)
2.17.m_cs$2$(not in LMFDB)
2.17.a_c$4$(not in LMFDB)

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.17.am_cs$2$(not in LMFDB)
2.17.m_cs$2$(not in LMFDB)
2.17.a_c$4$(not in LMFDB)
2.17.ag_t$6$(not in LMFDB)
2.17.g_t$6$(not in LMFDB)
2.17.ai_bg$8$(not in LMFDB)
2.17.i_bg$8$(not in LMFDB)