Properties

Label 2.16.ai_bl
Base Field $\F_{2^{4}}$
Dimension $2$
Ordinary Yes
$p$-rank $2$
Principally polarizable Yes
Contains a Jacobian Yes

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Invariants

Base field:  $\F_{2^{4}}$
Dimension:  $2$
L-polynomial:  $1 - 8 x + 37 x^{2} - 128 x^{3} + 256 x^{4}$
Frobenius angles:  $\pm0.132522875726$, $\pm0.472776187397$
Angle rank:  $2$ (numerical)
Number field:  4.0.1287440.3
Galois group:  $D_{4}$
Jacobians:  16

This isogeny class is simple and geometrically simple.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

This isogeny class contains the Jacobians of 16 curves, and hence is principally polarizable:

Point counts of the abelian variety

$r$ 1 2 3 4 5 6 7 8 9 10
$A(\F_{q^r})$ 158 67940 16751318 4266632000 1099672258158 281704737134660 72071122163901158 18446860746305312000 4722371034278166721598 1208928535686932465038500

Point counts of the curve

$r$ 1 2 3 4 5 6 7 8 9 10
$C(\F_{q^r})$ 9 267 4089 65103 1048729 16790907 268485849 4294994463 68719542969 1099514098027

Decomposition and endomorphism algebra

Endomorphism algebra over $\F_{2^{4}}$
The endomorphism algebra of this simple isogeny class is 4.0.1287440.3.
All geometric endomorphisms are defined over $\F_{2^{4}}$.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.
TwistExtension DegreeCommon base change
2.16.i_bl$2$2.256.k_agl