Properties

Label 2.71.ah_fm
Base field $\F_{71}$
Dimension $2$
$p$-rank $1$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $( 1 - 7 x + 71 x^{2} )( 1 + 71 x^{2} )$
  $1 - 7 x + 142 x^{2} - 497 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.363650862115$, $\pm0.5$
Angle rank:  $1$ (numerical)
Jacobians:  $112$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4680$ $26619840$ $128511882720$ $645533781984000$ $3255114593716947000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $65$ $5277$ $359060$ $25403033$ $1804157875$ $128100397662$ $9095121018685$ $645753529192273$ $45848500998757340$ $3255243553117837077$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 112 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{71^{2}}$.

Endomorphism algebra over $\F_{71}$
The isogeny class factors as 1.71.ah $\times$ 1.71.a and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{71}$
The base change of $A$ to $\F_{71^{2}}$ is 1.5041.dp $\times$ 1.5041.fm. The endomorphism algebra for each factor is:

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.h_fm$2$(not in LMFDB)