Properties

Label 2.67.u_ja
Base field $\F_{67}$
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:  $\F_{67}$
Dimension:  $2$
L-polynomial:  $( 1 + 10 x + 67 x^{2} )^{2}$
  $1 + 20 x + 234 x^{2} + 1340 x^{3} + 4489 x^{4}$
Frobenius angles:  $\pm0.709171043648$, $\pm0.709171043648$
Angle rank:  $1$ (numerical)
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6084$ $20466576$ $89852460516$ $406383023195136$ $1822809319723535364$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $88$ $4558$ $298744$ $20166766$ $1350104008$ $90457545022$ $6060721390504$ $406067635793758$ $27206534158316728$ $1822837809729656878$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 32 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{67}$.

Endomorphism algebra over $\F_{67}$
The isogeny class factors as 1.67.k 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-42}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.67.au_ja$2$(not in LMFDB)
2.67.a_bi$2$(not in LMFDB)
2.67.ak_bh$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.67.au_ja$2$(not in LMFDB)
2.67.a_bi$2$(not in LMFDB)
2.67.ak_bh$3$(not in LMFDB)
2.67.a_abi$4$(not in LMFDB)
2.67.k_bh$6$(not in LMFDB)