Properties

Label 2.41.as_gd
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:  $( 1 - 11 x + 41 x^{2} )( 1 - 7 x + 41 x^{2} )$
  $1 - 18 x + 159 x^{2} - 738 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.171113726078$, $\pm0.315918729109$
Angle rank:  $2$ (numerical)
Jacobians:  $12$
Isomorphism classes:  20

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1085$ $2817745$ $4787471360$ $7996560250105$ $13424283974457125$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $1676$ $69462$ $2829876$ $115870224$ $4750111118$ $194754296544$ $7984927976356$ $327381961744422$ $13422659370816476$

Jacobians and polarizations

This isogeny class contains the Jacobians of 12 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 isogeny class factors as 1.41.al $\times$ 1.41.ah and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. 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.ae_f$2$(not in LMFDB)
2.41.e_f$2$(not in LMFDB)
2.41.s_gd$2$(not in LMFDB)