Properties

Label 2.71.q_hy
Base field $\F_{71}$
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:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $( 1 + 8 x + 71 x^{2} )^{2}$
  $1 + 16 x + 206 x^{2} + 1136 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.657448017853$, $\pm0.657448017853$
Angle rank:  $1$ (numerical)
Jacobians:  $88$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6400$ $26214400$ $127249158400$ $645956789862400$ $3255433535524000000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $88$ $5198$ $355528$ $25419678$ $1804334648$ $128098873838$ $9095123963048$ $645753600924478$ $45848499890888728$ $3255243552683174798$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 88 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{71}$
The isogeny class factors as 1.71.i 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-55}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.71.aq_hy$2$(not in LMFDB)
2.71.a_da$2$(not in LMFDB)
2.71.ai_ah$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.71.aq_hy$2$(not in LMFDB)
2.71.a_da$2$(not in LMFDB)
2.71.ai_ah$3$(not in LMFDB)
2.71.a_ada$4$(not in LMFDB)
2.71.i_ah$6$(not in LMFDB)