Properties

Label 2.61.i_fe
Base field $\F_{61}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $( 1 + 2 x + 61 x^{2} )( 1 + 6 x + 61 x^{2} )$
  $1 + 8 x + 134 x^{2} + 488 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.540867587811$, $\pm0.625491882155$
Angle rank:  $2$ (numerical)
Jacobians:  $112$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4352$ $14622720$ $51239686400$ $191618228551680$ $713417516717050112$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $70$ $3926$ $225742$ $13839406$ $844684630$ $51520376198$ $3142738740190$ $191707326362206$ $11694146205191782$ $713342910965055926$

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 $\F_{61}$.

Endomorphism algebra over $\F_{61}$
The isogeny class factors as 1.61.c $\times$ 1.61.g and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. 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
2.61.ai_fe$2$(not in LMFDB)
2.61.ae_eg$2$(not in LMFDB)
2.61.e_eg$2$(not in LMFDB)