Properties

Label 2.71.aba_lx
Base field $\F_{71}$
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:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 - 26 x + 309 x^{2} - 1846 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.173356710192$, $\pm0.258712538951$
Angle rank:  $2$ (numerical)
Number field:  4.0.14912.2
Galois group:  $D_{4}$
Jacobians:  $9$
Isomorphism classes:  9

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3479$ $25128817$ $128454685604$ $646154585275913$ $3255476185108587559$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $46$ $4984$ $358900$ $25427460$ $1804358286$ $128100877030$ $9095119884274$ $645753499323588$ $45848500418096044$ $3255243549568776024$

Jacobians and polarizations

This isogeny class contains the Jacobians of 9 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{71}$.

Endomorphism algebra over $\F_{71}$
The endomorphism algebra of this simple isogeny class is 4.0.14912.2.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.71.ba_lx$2$(not in LMFDB)