Properties

Label 2.181.abu_big
Base field $\F_{181}$
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:  $\F_{181}$
Dimension:  $2$
L-polynomial:  $( 1 - 24 x + 181 x^{2} )( 1 - 22 x + 181 x^{2} )$
  $1 - 46 x + 890 x^{2} - 8326 x^{3} + 32761 x^{4}$
Frobenius angles:  $\pm0.149335043618$, $\pm0.195291079027$
Angle rank:  $2$ (numerical)
Jacobians:  $16$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $25280$ $1062366720$ $35164839608000$ $1152012181462548480$ $37738887442719518072000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $136$ $32426$ $5930248$ $1073353486$ $194265740776$ $35161849733978$ $6364291149864616$ $1151936659163311006$ $208500535058742351688$ $37738596846579535551626$

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 $\F_{181}$.

Endomorphism algebra over $\F_{181}$
The isogeny class factors as 1.181.ay $\times$ 1.181.aw 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
2.181.ac_agk$2$(not in LMFDB)
2.181.c_agk$2$(not in LMFDB)
2.181.bu_big$2$(not in LMFDB)