Properties

Label 2.191.abv_bjm
Base field $\F_{191}$
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:  $\F_{191}$
Dimension:  $2$
L-polynomial:  $( 1 - 27 x + 191 x^{2} )( 1 - 20 x + 191 x^{2} )$
  $1 - 47 x + 922 x^{2} - 8977 x^{3} + 36481 x^{4}$
Frobenius angles:  $\pm0.0686610702072$, $\pm0.242497774430$
Angle rank:  $2$ (numerical)
Jacobians:  $56$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $28380$ $1317626640$ $48545985795120$ $1771230810646440000$ $64615128331508560294500$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $145$ $36117$ $6967120$ $1330888553$ $254195217275$ $48551224431582$ $9273284094390125$ $1771197283448172913$ $338298681541989714160$ $64615048178041051967277$

Jacobians and polarizations

This isogeny class contains the Jacobians of 56 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{191}$.

Endomorphism algebra over $\F_{191}$
The isogeny class factors as 1.191.abb $\times$ 1.191.au 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
2.191.ah_agc$2$(not in LMFDB)
2.191.h_agc$2$(not in LMFDB)
2.191.bv_bjm$2$(not in LMFDB)