Properties

Label 2.17.ad_z
Base field $\F_{17}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{17}$
Dimension:  $2$
L-polynomial:  $1 - 3 x + 25 x^{2} - 51 x^{3} + 289 x^{4}$
Frobenius angles:  $\pm0.299661076636$, $\pm0.572186887130$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-218 +18 \sqrt{5}})\)
Galois group:  $D_{4}$
Jacobians:  $20$
Isomorphism classes:  28
Cyclic group of points:    no
Non-cyclic primes:   $3$

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $261$ $96309$ $24356781$ $6985195461$ $2019080699136$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $15$ $331$ $4959$ $83635$ $1422030$ $24131707$ $410259543$ $6975744739$ $118588889943$ $2015994917086$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 20 curves (of which all are hyperelliptic):

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

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{17}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-218 +18 \sqrt{5}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.17.d_z$2$(not in LMFDB)