Properties

Label 2.64.ax_jg
Base field $\F_{2^{6}}$
Dimension $2$
$p$-rank $1$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{2^{6}}$
Dimension:  $2$
L-polynomial:  $( 1 - 8 x )^{2}( 1 - 7 x + 64 x^{2} )$
  $1 - 23 x + 240 x^{2} - 1472 x^{3} + 4096 x^{4}$
Frobenius angles:  $0$, $0$, $\pm0.355864001265$
Angle rank:  $1$ (numerical)
Jacobians:  $3$

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

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2842$ $16574544$ $68712946666$ $281370287671200$ $1152797017209387802$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $42$ $4048$ $262122$ $16770976$ $1073625882$ $68718474736$ $4398042198858$ $281474972904256$ $18014398456831098$ $1152921502065981328$

Jacobians and polarizations

This isogeny class contains the Jacobians of 3 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2^{6}}$.

Endomorphism algebra over $\F_{2^{6}}$
The isogeny class factors as 1.64.aq $\times$ 1.64.ah 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
2.64.aj_q$2$(not in LMFDB)
2.64.j_q$2$(not in LMFDB)
2.64.x_jg$2$(not in LMFDB)
2.64.b_cu$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.64.aj_q$2$(not in LMFDB)
2.64.j_q$2$(not in LMFDB)
2.64.x_jg$2$(not in LMFDB)
2.64.b_cu$3$(not in LMFDB)
2.64.ah_ey$4$(not in LMFDB)
2.64.h_ey$4$(not in LMFDB)
2.64.ap_hc$6$(not in LMFDB)
2.64.ab_cu$6$(not in LMFDB)
2.64.p_hc$6$(not in LMFDB)