Properties

Label 2.17.g_bq
Base field $\F_{17}$
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:  $\F_{17}$
Dimension:  $2$
L-polynomial:  $( 1 + 2 x + 17 x^{2} )( 1 + 4 x + 17 x^{2} )$
  $1 + 6 x + 42 x^{2} + 102 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.577979130377$, $\pm0.661206336803$
Angle rank:  $2$ (numerical)
Jacobians:  $8$
Isomorphism classes:  30
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $440$ $98560$ $23010680$ $6970163200$ $2021119806200$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $338$ $4680$ $83454$ $1423464$ $24128786$ $410314488$ $6975923326$ $118587750840$ $2015992692818$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 8 curves (of which all are hyperelliptic):

  • $y^2=12 x^5+13 x^4+5 x^3+13 x^2+12 x$
  • $y^2=2 x^6+8 x^5+6 x^4+16 x^3+5 x^2+15 x+1$
  • $y^2=6 x^6+6 x^5+6 x^4+6 x^3+7 x^2+11 x+10$
  • $y^2=7 x^6+15 x^5+14 x^4+8 x^3+14 x^2+15 x+7$
  • $y^2=16 x^6+16 x^5+10 x^4+14 x^3+10 x^2+16 x+16$
  • $y^2=15 x^6+3 x^5+x^4+13 x^3+9 x^2+5 x+4$
  • $y^2=x^6+11 x^5+6 x^4+3 x^3+6 x^2+11 x+1$
  • $y^2=15 x^6+4 x^5+14 x^4+4 x^3+14 x^2+4 x+15$

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{17}$.

Endomorphism algebra over $\F_{17}$
The isogeny class factors as 1.17.c $\times$ 1.17.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
2.17.ag_bq$2$(not in LMFDB)
2.17.ac_ba$2$(not in LMFDB)
2.17.c_ba$2$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.17.ag_bq$2$(not in LMFDB)
2.17.ac_ba$2$(not in LMFDB)
2.17.c_ba$2$(not in LMFDB)
2.17.am_co$4$(not in LMFDB)
2.17.ae_c$4$(not in LMFDB)
2.17.e_c$4$(not in LMFDB)
2.17.m_co$4$(not in LMFDB)