Properties

Label 2.41.au_ha
Base field $\F_{41}$
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:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $( 1 - 10 x + 41 x^{2} )^{2}$
  $1 - 20 x + 182 x^{2} - 820 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.214776712523$, $\pm0.214776712523$
Angle rank:  $1$ (numerical)
Jacobians:  $10$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1024$ $2768896$ $4781999104$ $8002109440000$ $13427514355631104$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $22$ $1646$ $69382$ $2831838$ $115898102$ $4750274126$ $194754254822$ $7984918073278$ $327381863616982$ $13422658895772206$

Jacobians and polarizations

This isogeny class contains the Jacobians of 10 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41}$.

Endomorphism algebra over $\F_{41}$
The isogeny class factors as 1.41.ak 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-1}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.41.a_as$2$(not in LMFDB)
2.41.u_ha$2$(not in LMFDB)
2.41.k_ch$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.41.a_as$2$(not in LMFDB)
2.41.u_ha$2$(not in LMFDB)
2.41.k_ch$3$(not in LMFDB)
2.41.as_gg$4$(not in LMFDB)
2.41.aq_fq$4$(not in LMFDB)
2.41.ac_c$4$(not in LMFDB)
2.41.a_s$4$(not in LMFDB)
2.41.c_c$4$(not in LMFDB)
2.41.q_fq$4$(not in LMFDB)
2.41.s_gg$4$(not in LMFDB)
2.41.ak_ch$6$(not in LMFDB)
2.41.a_adc$8$(not in LMFDB)
2.41.a_dc$8$(not in LMFDB)
2.41.ai_x$12$(not in LMFDB)
2.41.i_x$12$(not in LMFDB)