Properties

Label 2.41.g_dn
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:  $( 1 + 3 x + 41 x^{2} )^{2}$
  $1 + 6 x + 91 x^{2} + 246 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.575266912322$, $\pm0.575266912322$
Angle rank:  $1$ (numerical)
Jacobians:  $34$
Cyclic group of points:    no
Non-cyclic primes:   $3, 5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2025$ $3080025$ $4703216400$ $7973818202025$ $13427276345015625$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $1828$ $68238$ $2821828$ $115896048$ $4750145998$ $194752514928$ $7984928793988$ $327381995816478$ $13422658979725348$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 34 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.d 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-155}) \)$)$

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.ag_dn$2$(not in LMFDB)
2.41.a_cv$2$(not in LMFDB)
2.41.ad_abg$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.41.ag_dn$2$(not in LMFDB)
2.41.a_cv$2$(not in LMFDB)
2.41.ad_abg$3$(not in LMFDB)
2.41.a_acv$4$(not in LMFDB)
2.41.d_abg$6$(not in LMFDB)