Properties

Label 2.41.ac_de
Base field $\F_{41}$
Dimension $2$
$p$-rank $1$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $( 1 - 2 x + 41 x^{2} )( 1 + 41 x^{2} )$
  $1 - 2 x + 82 x^{2} - 82 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.450084017046$, $\pm0.5$
Angle rank:  $1$ (numerical)
Jacobians:  $64$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1680$ $3104640$ $4766645520$ $7967748096000$ $13420898295882000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $40$ $1842$ $69160$ $2819678$ $115841000$ $4750323282$ $194755059560$ $7984917819838$ $327381898665640$ $13422659542476402$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 64 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41^{2}}$.

Endomorphism algebra over $\F_{41}$
The isogeny class factors as 1.41.ac $\times$ 1.41.a and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{41}$
The base change of $A$ to $\F_{41^{2}}$ is 1.1681.da $\times$ 1.1681.de. 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
2.41.c_de$2$(not in LMFDB)