Properties

Label 2.191.abx_blt
Base field $\F_{191}$
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:  $\F_{191}$
Dimension:  $2$
L-polynomial:  $1 - 49 x + 981 x^{2} - 9359 x^{3} + 36481 x^{4}$
Frobenius angles:  $\pm0.122524293102$, $\pm0.179046122411$
Angle rank:  $2$ (numerical)
Number field:  4.0.585125.1
Galois group:  $D_{4}$
Jacobians:  $16$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $28055$ $1314965905$ $48540654699605$ $1771255261948841405$ $64615379546177676250000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $143$ $36043$ $6966353$ $1330906923$ $254196205548$ $48551249214343$ $9273284526492143$ $1771197288870081603$ $338298681581845835573$ $64615048177862676323598$

Jacobians and polarizations

This isogeny class contains the Jacobians of 16 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 endomorphism algebra of this simple isogeny class is 4.0.585125.1.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.191.bx_blt$2$(not in LMFDB)