Properties

Label 2.17.ai_by
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:  $( 1 - 4 x + 17 x^{2} )^{2}$
  $1 - 8 x + 50 x^{2} - 136 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.338793663197$, $\pm0.338793663197$
Angle rank:  $1$ (numerical)
Jacobians:  $5$
Cyclic group of points:    no
Non-cyclic primes:   $2, 7$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $196$ $94864$ $25542916$ $7018418176$ $2012125228036$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $10$ $326$ $5194$ $84030$ $1417130$ $24118022$ $410306858$ $6975962494$ $118589237578$ $2015995858886$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 5 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{17}$
The isogeny class factors as 1.17.ae 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-13}) \)$)$

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_s$2$(not in LMFDB)
2.17.i_by$2$(not in LMFDB)
2.17.e_ab$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.17.a_s$2$(not in LMFDB)
2.17.i_by$2$(not in LMFDB)
2.17.e_ab$3$(not in LMFDB)
2.17.a_as$4$(not in LMFDB)
2.17.ae_ab$6$(not in LMFDB)