Properties

Label 2.17.a_bi
Base field $\F_{17}$
Dimension $2$
$p$-rank $0$
Ordinary no
Supersingular yes
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:  $( 1 + 17 x^{2} )^{2}$
  $1 + 34 x^{2} + 289 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.5$
Angle rank:  $0$ (numerical)
Jacobians:  $14$

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

Newton polygon

This isogeny class is supersingular.

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $324$ $104976$ $24147396$ $6879707136$ $2015996740164$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $18$ $358$ $4914$ $82366$ $1419858$ $24157222$ $410338674$ $6975423358$ $118587876498$ $2015999579878$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 14 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 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-17}) \)$)$
Endomorphism algebra over $\overline{\F}_{17}$
The base change of $A$ to $\F_{17^{2}}$ is 1.289.bi 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $17$ and $\infty$.

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.a_ar$3$(not in LMFDB)
2.17.a_abi$4$(not in LMFDB)
2.17.a_a$8$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.17.a_ar$3$(not in LMFDB)
2.17.a_abi$4$(not in LMFDB)
2.17.a_a$8$(not in LMFDB)
2.17.a_r$12$(not in LMFDB)