Properties

Label 2.71.g_eg
Base field $\F_{71}$
Dimension $2$
$p$-rank $2$
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:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 + 6 x + 110 x^{2} + 426 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.435275962254$, $\pm0.688420648946$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-234 +6 \sqrt{41}})\)
Galois group:  $D_{4}$
Jacobians:  $192$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $5584$ $26356480$ $127926251536$ $645760749035520$ $3255140939768066704$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $78$ $5226$ $357426$ $25411966$ $1804172478$ $128099873418$ $9095131206498$ $645753532909246$ $45848499954753006$ $3255243552771931626$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 192 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{71}$.

Endomorphism algebra over $\F_{71}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-234 +6 \sqrt{41}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.71.ag_eg$2$(not in LMFDB)