Properties

Label 4.2.ac_a_e_ag
Base field $\F_{2}$
Dimension $4$
$p$-rank $0$
Ordinary no
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Contains a Jacobian no

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Invariants

Base field:  $\F_{2}$
Dimension:  $4$
L-polynomial:  $1 - 2 x + 4 x^{3} - 6 x^{4} + 8 x^{5} - 16 x^{7} + 16 x^{8}$
Frobenius angles:  $\pm0.133582184824$, $\pm0.190415260312$, $\pm0.513309389920$, $\pm0.956476314431$
Angle rank:  $3$ (numerical)
Number field:  8.0.214798336.3
Galois group:  $S_4\times C_2$
Jacobians:  $0$
Isomorphism classes:  2

This isogeny class is simple and geometrically simple, primitive, not ordinary, and not supersingular.

Newton polygon

$p$-rank:  $0$
Slopes:  $[1/4, 1/4, 1/4, 1/4, 3/4, 3/4, 3/4, 3/4]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $5$ $85$ $8765$ $37825$ $2524525$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $1$ $1$ $13$ $9$ $61$ $97$ $169$ $241$ $553$ $1041$

Jacobians and polarizations

This isogeny class does not contain a Jacobian, and it is unknown whether it is principally polarizable.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2}$.

Endomorphism algebra over $\F_{2}$
The endomorphism algebra of this simple isogeny class is 8.0.214798336.3.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
4.2.c_a_ae_ag$2$4.4.ae_e_q_aci
4.2.ac_e_ai_k$4$(not in LMFDB)
4.2.c_e_i_k$4$(not in LMFDB)