Properties

Label 2.71.abb_md
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:  $1 - 27 x + 315 x^{2} - 1917 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.0612390793144$, $\pm0.286887128510$
Angle rank:  $2$ (numerical)
Number field:  4.0.50653.1
Galois group:  $C_4$
Jacobians:  $7$
Isomorphism classes:  7

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3413$ $24918313$ $128128904003$ $645798673326877$ $3255187240167623408$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $45$ $4943$ $357993$ $25413459$ $1804198140$ $128099535779$ $9095112788499$ $645753499132435$ $45848500896055059$ $3255243555564245918$

Jacobians and polarizations

This isogeny class contains the Jacobians of 7 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 4.0.50653.1.

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.bb_md$2$(not in LMFDB)