Properties

Label 2.19.e_bl
Base field $\F_{19}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{19}$
Dimension:  $2$
L-polynomial:  $1 + 4 x + 37 x^{2} + 76 x^{3} + 361 x^{4}$
Frobenius angles:  $\pm0.491379479278$, $\pm0.661511841390$
Angle rank:  $2$ (numerical)
Number field:  4.0.110225.1
Galois group:  $D_{4}$
Jacobians:  $22$
Isomorphism classes:  22

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $479$ $152801$ $46014656$ $16931726009$ $6134447850399$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $420$ $6708$ $129924$ $2477464$ $47045766$ $893906856$ $16983466884$ $322686299532$ $6131072781700$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 22 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{19}$.

Endomorphism algebra over $\F_{19}$
The endomorphism algebra of this simple isogeny class is 4.0.110225.1.

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.ae_bl$2$(not in LMFDB)