Properties

Label 2.41.c_ba
Base field $\F_{41}$
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:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $1 + 2 x + 26 x^{2} + 82 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.329106270139$, $\pm0.732691122929$
Angle rank:  $2$ (numerical)
Number field:  4.0.558828.2
Galois group:  $D_{4}$
Jacobians:  $160$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1792$ $2910208$ $4756772608$ $7999393497088$ $13420333481535232$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1730$ $69020$ $2830878$ $115836124$ $4749922658$ $194754574828$ $7984922394814$ $327381980878988$ $13422659571439490$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 160 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41}$.

Endomorphism algebra over $\F_{41}$
The endomorphism algebra of this simple isogeny class is 4.0.558828.2.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.41.ac_ba$2$(not in LMFDB)