Properties

Label 2.41.as_fx
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

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Invariants

Base field:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $1 - 18 x + 153 x^{2} - 738 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.101373436493$, $\pm0.349335512379$
Angle rank:  $2$ (numerical)
Number field:  4.0.3342400.2
Galois group:  $D_{4}$
Jacobians:  $6$
Isomorphism classes:  12

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1079$ $2795689$ $4764971900$ $7985161545049$ $13420968266033159$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $1664$ $69138$ $2825844$ $115841604$ $4750018598$ $194754663204$ $7984934429284$ $327382001764578$ $13422659546485904$

Jacobians and polarizations

This isogeny class contains the Jacobians of 6 curves (of which all are hyperelliptic), and hence is principally polarizable:

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 4.0.3342400.2.

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.s_fx$2$(not in LMFDB)