Properties

Label 2.79.ad_fa
Base field $\F_{79}$
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:  $\F_{79}$
Dimension:  $2$
L-polynomial:  $( 1 - 7 x + 79 x^{2} )( 1 + 4 x + 79 x^{2} )$
  $1 - 3 x + 130 x^{2} - 237 x^{3} + 6241 x^{4}$
Frobenius angles:  $\pm0.371166915609$, $\pm0.572243955238$
Angle rank:  $2$ (numerical)
Jacobians:  $112$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6132$ $40544784$ $243300271536$ $1516833077659200$ $9468278561933511852$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $77$ $6493$ $493472$ $38943001$ $3077057207$ $243086914366$ $19203902883473$ $1517108906332561$ $119851596931955168$ $9468276074870495653$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 112 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79}$.

Endomorphism algebra over $\F_{79}$
The isogeny class factors as 1.79.ah $\times$ 1.79.e 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 are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.79.al_he$2$(not in LMFDB)
2.79.d_fa$2$(not in LMFDB)
2.79.l_he$2$(not in LMFDB)
2.79.ay_kr$3$(not in LMFDB)
2.79.g_cp$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.79.al_he$2$(not in LMFDB)
2.79.d_fa$2$(not in LMFDB)
2.79.l_he$2$(not in LMFDB)
2.79.ay_kr$3$(not in LMFDB)
2.79.g_cp$3$(not in LMFDB)
2.79.au_jp$6$(not in LMFDB)
2.79.ak_bn$6$(not in LMFDB)
2.79.ag_cp$6$(not in LMFDB)
2.79.k_bn$6$(not in LMFDB)
2.79.u_jp$6$(not in LMFDB)
2.79.y_kr$6$(not in LMFDB)