Properties

Label 2.157.abs_beo
Base field $\F_{157}$
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:  $\F_{157}$
Dimension:  $2$
L-polynomial:  $( 1 - 24 x + 157 x^{2} )( 1 - 20 x + 157 x^{2} )$
  $1 - 44 x + 794 x^{2} - 6908 x^{3} + 24649 x^{4}$
Frobenius angles:  $\pm0.0929086555916$, $\pm0.205845557398$
Angle rank:  $2$ (numerical)
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $18492$ $599066832$ $14971819109436$ $369158899399041024$ $9099112025167481580252$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $114$ $24302$ $3868794$ $607595758$ $95389538994$ $14976078944222$ $2351243339560026$ $369145194873633886$ $57955795547652591858$ $9099059901037894613582$

Jacobians and polarizations

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

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{157}$.

Endomorphism algebra over $\F_{157}$
The isogeny class factors as 1.157.ay $\times$ 1.157.au 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
2.157.ae_agk$2$(not in LMFDB)
2.157.e_agk$2$(not in LMFDB)
2.157.bs_beo$2$(not in LMFDB)