Properties

Label 2.19.c_w
Base field $\F_{19}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{19}$
Dimension:  $2$
L-polynomial:  $1 + 2 x + 22 x^{2} + 38 x^{3} + 361 x^{4}$
Frobenius angles:  $\pm0.383375326127$, $\pm0.699950925866$
Angle rank:  $2$ (numerical)
Number field:  4.0.238136.1
Galois group:  $D_{4}$
Jacobians:  $40$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $424$ $145856$ $46967752$ $17049982976$ $6123548810824$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $22$ $402$ $6850$ $130830$ $2473062$ $47026722$ $893961202$ $16983737694$ $322687205110$ $6131066918002$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 40 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{19}$.

Endomorphism algebra over $\F_{19}$
The endomorphism algebra of this simple isogeny class is 4.0.238136.1.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.19.ac_w$2$(not in LMFDB)