Properties

Label 2.41.ak_ed
Base field $\F_{41}$
Dimension $2$
$p$-rank $2$
Ordinary yes
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:  $( 1 - 5 x + 41 x^{2} )^{2}$
  $1 - 10 x + 107 x^{2} - 410 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.372324822061$, $\pm0.372324822061$
Angle rank:  $1$ (numerical)
Jacobians:  $21$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1369$ $3024121$ $4818025744$ $7985569515625$ $13418135738402329$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $32$ $1796$ $69902$ $2825988$ $115817152$ $4749899726$ $194754852352$ $7984936506628$ $327381967064222$ $13422659011125956$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 21 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{41}$
The isogeny class factors as 1.41.af 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-139}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.41.a_cf$2$(not in LMFDB)
2.41.k_ed$2$(not in LMFDB)
2.41.f_aq$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.41.a_cf$2$(not in LMFDB)
2.41.k_ed$2$(not in LMFDB)
2.41.f_aq$3$(not in LMFDB)
2.41.a_acf$4$(not in LMFDB)
2.41.af_aq$6$(not in LMFDB)