Properties

Label 2.41.c_bi
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:  $( 1 - 6 x + 41 x^{2} )( 1 + 8 x + 41 x^{2} )$
  $1 + 2 x + 34 x^{2} + 82 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.344786929280$, $\pm0.714776712523$
Angle rank:  $2$ (numerical)
Jacobians:  $170$
Cyclic group of points:    no
Non-cyclic primes:   $2, 5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1800$ $2937600$ $4753441800$ $7997040230400$ $13420472477445000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1746$ $68972$ $2830046$ $115837324$ $4749884658$ $194754919564$ $7984925750206$ $327381961138412$ $13422659555121426$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 170 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{41}$
The isogeny class factors as 1.41.ag $\times$ 1.41.i 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
2.41.ao_fa$2$(not in LMFDB)
2.41.ac_bi$2$(not in LMFDB)
2.41.o_fa$2$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.41.ao_fa$2$(not in LMFDB)
2.41.ac_bi$2$(not in LMFDB)
2.41.o_fa$2$(not in LMFDB)
2.41.aq_fm$4$(not in LMFDB)
2.41.ae_w$4$(not in LMFDB)
2.41.e_w$4$(not in LMFDB)
2.41.q_fm$4$(not in LMFDB)