Properties

Label 2.41.ao_du
Base field $\F_{41}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $1 - 14 x + 98 x^{2} - 574 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.0312551325813$, $\pm0.468744867419$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{33})\)
Galois group:  $C_2^2$
Jacobians:  $16$
Isomorphism classes:  30
Cyclic group of points:    no
Non-cyclic primes:   $2$

This isogeny class is simple but not geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1192$ $2822656$ $4726042792$ $7967386894336$ $13419284379958312$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $28$ $1682$ $68572$ $2819550$ $115827068$ $4750104242$ $194754151676$ $7984917237694$ $327381883464412$ $13422659310152402$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 16 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41^{4}}$.

Endomorphism algebra over $\F_{41}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{33})\).
Endomorphism algebra over $\overline{\F}_{41}$
The base change of $A$ to $\F_{41^{4}}$ is 1.2825761.aepm 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-33}) \)$)$
Remainder of endomorphism lattice by field

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.41.o_du$2$(not in LMFDB)
2.41.a_aq$8$(not in LMFDB)
2.41.a_q$8$(not in LMFDB)