Properties

Label 2.71.p_ew
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:  $( 1 - x + 71 x^{2} )( 1 + 16 x + 71 x^{2} )$
  $1 + 15 x + 126 x^{2} + 1065 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.481100681038$, $\pm0.898333180169$
Angle rank:  $2$ (numerical)
Jacobians:  $54$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6248$ $25541824$ $128423266400$ $645430551910144$ $3255194705163903128$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $87$ $5069$ $358812$ $25398969$ $1804202277$ $128101197278$ $9095118871947$ $645753528380689$ $45848500087278132$ $3255243557604280229$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 54 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.ab $\times$ 1.71.q and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

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.ar_gc$2$(not in LMFDB)
2.71.ap_ew$2$(not in LMFDB)
2.71.r_gc$2$(not in LMFDB)