Properties

Label 2.17.ab_bc
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:  $( 1 - 3 x + 17 x^{2} )( 1 + 2 x + 17 x^{2} )$
  $1 - x + 28 x^{2} - 17 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.381477984739$, $\pm0.577979130377$
Angle rank:  $2$ (numerical)
Jacobians:  $21$
Isomorphism classes:  138

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $300$ $100800$ $24292800$ $6945120000$ $2015933407500$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $17$ $345$ $4946$ $83153$ $1419817$ $24132510$ $410319241$ $6975985633$ $118588574642$ $2015989341225$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 21 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.ad $\times$ 1.17.c 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 are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.17.af_bo$2$(not in LMFDB)
2.17.b_bc$2$(not in LMFDB)
2.17.f_bo$2$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.17.af_bo$2$(not in LMFDB)
2.17.b_bc$2$(not in LMFDB)
2.17.f_bo$2$(not in LMFDB)
2.17.al_cg$4$(not in LMFDB)
2.17.af_k$4$(not in LMFDB)
2.17.f_k$4$(not in LMFDB)
2.17.l_cg$4$(not in LMFDB)