Properties

Label 2.71.d_fa
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:  $1 + 3 x + 130 x^{2} + 213 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.456899286358$, $\pm0.601336920172$
Angle rank:  $2$ (numerical)
Number field:  4.0.58017393.1
Galois group:  $D_{4}$
Jacobians:  $128$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $5388$ $26702928$ $127920150288$ $645459009959232$ $3255300767623547508$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $75$ $5293$ $357408$ $25400089$ $1804261065$ $128100537934$ $9095120283639$ $645753549533905$ $45848500433332704$ $3255243548180619493$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 128 curves (of which all are hyperelliptic):

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 4.0.58017393.1.

Base change

This is a primitive isogeny class.

Twists

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

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