Properties

Label 2.157.abr_bdl
Base field $\F_{157}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{157}$
Dimension:  $2$
L-polynomial:  $1 - 43 x + 765 x^{2} - 6751 x^{3} + 24649 x^{4}$
Frobenius angles:  $\pm0.0408247231830$, $\pm0.242255315239$
Angle rank:  $2$ (numerical)
Number field:  4.0.76725.1
Galois group:  $D_{4}$
Jacobians:  $16$

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $18621$ $599763789$ $14971910056641$ $369148907776102821$ $9099059097050910510336$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $115$ $24331$ $3868819$ $607579315$ $95388984130$ $14976067398307$ $2351243161126303$ $369145192751482819$ $57955795529013965383$ $9099059900939207148886$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 16 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{157}$
The endomorphism algebra of this simple isogeny class is 4.0.76725.1.

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.br_bdl$2$(not in LMFDB)