Properties

Label 2.17.ak_cd
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:  $( 1 - 7 x + 17 x^{2} )( 1 - 3 x + 17 x^{2} )$
  $1 - 10 x + 55 x^{2} - 170 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.177280642489$, $\pm0.381477984739$
Angle rank:  $2$ (numerical)
Jacobians:  $18$
Isomorphism classes:  30

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $165$ $86625$ $24837120$ $7001465625$ $2015920649325$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $8$ $300$ $5054$ $83828$ $1419808$ $24141150$ $410388784$ $6975964708$ $118587816158$ $2015989381500$

Jacobians and polarizations

This isogeny class contains the Jacobians of 18 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{17}$
The isogeny class factors as 1.17.ah $\times$ 1.17.ad and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.17.ae_n$2$(not in LMFDB)
2.17.e_n$2$(not in LMFDB)
2.17.k_cd$2$(not in LMFDB)