Properties

Label 2.19.al_cn
Base Field $\F_{19}$
Dimension $2$
Ordinary Yes
$p$-rank $2$
Principally polarizable Yes
Contains a Jacobian Yes

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Invariants

Base field:  $\F_{19}$
Dimension:  $2$
L-polynomial:  $1 - 11 x + 65 x^{2} - 209 x^{3} + 361 x^{4}$
Frobenius angles:  $\pm0.183908064930$, $\pm0.360590248890$
Angle rank:  $2$ (numerical)
Number field:  4.0.26533.1
Galois group:  $D_{4}$
Jacobians:  5

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 5 curves, and hence is principally polarizable:

Point counts of the abelian variety

$r$ 1 2 3 4 5 6 7 8 9 10
$A(\F_{q^r})$ 207 133929 48346713 17064295677 6132261832272 2213364397163049 799043845092737661 288445952175817883733 104127441596475871887171 37589936977009790399856384

Point counts of the curve

$r$ 1 2 3 4 5 6 7 8 9 10
$C(\F_{q^r})$ 9 371 7047 130939 2476584 47046935 893913309 16983830275 322687980711 6131060307686

Decomposition and endomorphism algebra

Endomorphism algebra over $\F_{19}$
The endomorphism algebra of this simple isogeny class is 4.0.26533.1.
All geometric endomorphisms are defined over $\F_{19}$.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.
TwistExtension DegreeCommon base change
2.19.l_cn$2$(not in LMFDB)