Properties

Label 2.79.h_gc
Base field $\F_{79}$
Dimension $2$
$p$-rank $1$
Ordinary no
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:  $( 1 + 79 x^{2} )( 1 + 7 x + 79 x^{2} )$
  $1 + 7 x + 158 x^{2} + 553 x^{3} + 6241 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.628833084391$
Angle rank:  $1$ (numerical)
Jacobians:  $80$
Cyclic group of points:    no
Non-cyclic primes:   $2$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6960$ $40646400$ $242439600960$ $1516646114380800$ $9468583046696254800$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $87$ $6509$ $491724$ $38938201$ $3077156157$ $243087695822$ $19203906325803$ $1517108809545361$ $119851595650013796$ $9468276084983613749$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 80 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79^{2}}$.

Endomorphism algebra over $\F_{79}$
The isogeny class factors as 1.79.a $\times$ 1.79.h and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{79}$
The base change of $A$ to $\F_{79^{2}}$ is 1.6241.ef $\times$ 1.6241.gc. 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
2.79.ah_gc$2$(not in LMFDB)