Properties

Label 2.41.e_az
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

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Invariants

Base field:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $1 + 4 x - 25 x^{2} + 164 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.267782001470$, $\pm0.934448668136$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-37})\)
Galois group:  $C_2^2$
Jacobians:  $4$
Cyclic group of points:    no
Non-cyclic primes:   $5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1825$ $2717425$ $4809422500$ $7987732198825$ $13425153346470625$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $46$ $1616$ $69778$ $2826756$ $115877726$ $4750013558$ $194753572766$ $7984920565636$ $327381914210338$ $13422659541722576$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 4 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41^{3}}$.

Endomorphism algebra over $\F_{41}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-37})\).
Endomorphism algebra over $\overline{\F}_{41}$
The base change of $A$ to $\F_{41^{3}}$ is 1.68921.qm 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-37}) \)$)$

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.ae_az$2$(not in LMFDB)
2.41.ai_du$3$(not in LMFDB)
2.41.a_co$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.41.ae_az$2$(not in LMFDB)
2.41.ai_du$3$(not in LMFDB)
2.41.a_co$6$(not in LMFDB)
2.41.i_du$6$(not in LMFDB)
2.41.a_aco$12$(not in LMFDB)