Properties

Label 2.191.acb_bps
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 no

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Invariants

Base field:  $\F_{191}$
Dimension:  $2$
L-polynomial:  $( 1 - 27 x + 191 x^{2} )( 1 - 26 x + 191 x^{2} )$
  $1 - 53 x + 1084 x^{2} - 10123 x^{3} + 36481 x^{4}$
Frobenius angles:  $\pm0.0686610702072$, $\pm0.110219473395$
Angle rank:  $2$ (numerical)
Jacobians:  $0$

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

Newton polygon

This isogeny class is ordinary.

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $27390$ $1307653380$ $48503242850040$ $1771116211426367520$ $64614968004475421222250$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $139$ $35841$ $6960982$ $1330802441$ $254194586549$ $48551229231498$ $9273284351441459$ $1771197288542903281$ $338298681609668585002$ $64615048178642180519001$

Jacobians and polarizations

This isogeny class is principally polarizable, but does not contain a Jacobian.

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.aba 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.ab_ami$2$(not in LMFDB)
2.191.b_ami$2$(not in LMFDB)
2.191.cb_bps$2$(not in LMFDB)