Properties

Label 1.41.h
Base field $\F_{41}$
Dimension $1$
$p$-rank $1$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{41}$
Dimension:  $1$
L-polynomial:  $1 + 7 x + 41 x^{2}$
Frobenius angles:  $\pm0.684081270891$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-115}) \)
Galois group:  $C_2$
Jacobians:  $2$
Isomorphism classes:  2
Cyclic group of points:    yes

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

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $1$
Slopes:  $[0, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $49$ $1715$ $68404$ $2828035$ $115861529$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $49$ $1715$ $68404$ $2828035$ $115861529$ $4749973760$ $194754968849$ $7984925714115$ $327381902505364$ $13422659513487875$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 2 curves (of which 0 are hyperelliptic):

  • $y^2=x^3+28 x+28$
  • $y^2=x^3+9 x+27$

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{41}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-115}) \).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
1.41.ah$2$(not in LMFDB)