Properties

Label 2.17.e_bi
Base field $\F_{17}$
Dimension $2$
$p$-rank $1$
Ordinary no
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:  $( 1 + 17 x^{2} )( 1 + 4 x + 17 x^{2} )$
  $1 + 4 x + 34 x^{2} + 68 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.661206336803$
Angle rank:  $1$ (numerical)
Jacobians:  $32$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $396$ $99792$ $23459436$ $6948716544$ $2017933426476$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $22$ $342$ $4774$ $83198$ $1421222$ $24137622$ $410354582$ $6975692926$ $118587195958$ $2015997719382$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 32 curves (of which all are hyperelliptic):

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.a $\times$ 1.17.e 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.s $\times$ 1.289.bi. 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_bi$2$(not in LMFDB)