Properties

Label 4.4.ak_by_agg_on
Base field $\F_{2^{2}}$
Dimension $4$
$p$-rank $4$
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:  $\F_{2^{2}}$
Dimension:  $4$
L-polynomial:  $( 1 - 3 x + 4 x^{2} )^{2}( 1 - 4 x + 9 x^{2} - 16 x^{3} + 16 x^{4} )$
  $1 - 10 x + 50 x^{2} - 162 x^{3} + 377 x^{4} - 648 x^{5} + 800 x^{6} - 640 x^{7} + 256 x^{8}$
Frobenius angles:  $\pm0.117169895439$, $\pm0.230053456163$, $\pm0.230053456163$, $\pm0.478661301576$
Angle rank:  $3$ (numerical)

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

Newton polygon

This isogeny class is ordinary.

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $24$ $70656$ $21586392$ $4761649152$ $1224771644184$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-5$ $17$ $79$ $285$ $1135$ $4385$ $16543$ $64701$ $260575$ $1049537$

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 $\F_{2^{2}}$.

Endomorphism algebra over $\F_{2^{2}}$
The isogeny class factors as 1.4.ad 2 $\times$ 2.4.ae_j 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 are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
4.4.ae_i_am_x$2$(not in LMFDB)
4.4.ac_c_g_ah$2$(not in LMFDB)
4.4.c_c_ag_ah$2$(not in LMFDB)
4.4.e_i_m_x$2$(not in LMFDB)
4.4.k_by_gg_on$2$(not in LMFDB)
4.4.ab_c_d_at$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.4.ae_i_am_x$2$(not in LMFDB)
4.4.ac_c_g_ah$2$(not in LMFDB)
4.4.c_c_ag_ah$2$(not in LMFDB)
4.4.e_i_m_x$2$(not in LMFDB)
4.4.k_by_gg_on$2$(not in LMFDB)
4.4.ab_c_d_at$3$(not in LMFDB)
4.4.ae_k_au_bp$4$(not in LMFDB)
4.4.e_k_u_bp$4$(not in LMFDB)
4.4.ah_ba_acx_gr$6$(not in LMFDB)
4.4.b_c_ad_at$6$(not in LMFDB)
4.4.h_ba_cx_gr$6$(not in LMFDB)