Properties

Label 2.41.c_ap
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:  $1 + 2 x - 15 x^{2} + 82 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.255433653965$, $\pm0.824068551096$
Angle rank:  $2$ (numerical)
Number field:  4.0.245312.1
Galois group:  $D_{4}$
Jacobians:  $45$
Isomorphism classes:  45

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1751$ $2771833$ $4773933404$ $8000089351097$ $13421948139018631$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1648$ $69266$ $2831124$ $115850064$ $4750225894$ $194752920560$ $7984921250340$ $327381922394210$ $13422659180945568$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 45 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 4.0.245312.1.

Base change

This is a primitive isogeny class.

Twists

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

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