Properties

Label 5.2.ab_c_b_a_d
Base field $\F_{2}$
Dimension $5$
$p$-rank $5$
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:  $\F_{2}$
Dimension:  $5$
L-polynomial:  $( 1 - x + 2 x^{2} )( 1 + x^{3} + x^{4} + 2 x^{5} + 16 x^{8} )$
  $1 - x + 2 x^{2} + x^{3} + 3 x^{5} + 4 x^{7} + 16 x^{8} - 16 x^{9} + 32 x^{10}$
Frobenius angles:  $\pm0.160761046163$, $\pm0.352134945401$, $\pm0.384973271919$, $\pm0.624242320844$, $\pm0.891697068324$
Angle rank:  $5$ (numerical)
Jacobians:  $0$
Isomorphism classes:  30

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

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $5$
Slopes:  $[0, 0, 0, 0, 0, 1, 1, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $42$ $2520$ $80262$ $1638000$ $31522722$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $2$ $8$ $17$ $20$ $32$ $53$ $135$ $396$ $503$ $958$

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 $\F_{2}$.

Endomorphism algebra over $\F_{2}$
The isogeny class factors as 1.2.ab $\times$ 4.2.a_a_b_b 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
5.2.ab_c_ab_c_af$2$(not in LMFDB)
5.2.b_c_ab_a_ad$2$(not in LMFDB)
5.2.b_c_b_c_f$2$(not in LMFDB)