Properties

Label 2.67.c_cs
Base field $\F_{67}$
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:  $\F_{67}$
Dimension:  $2$
L-polynomial:  $1 + 2 x + 70 x^{2} + 134 x^{3} + 4489 x^{4}$
Frobenius angles:  $\pm0.358021167718$, $\pm0.686733147249$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-202 +2 \sqrt{65}})\)
Galois group:  $D_{4}$
Jacobians:  $240$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4696$ $20775104$ $90454826296$ $406232727197696$ $1822779915704554936$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $70$ $4626$ $300754$ $20159310$ $1350082230$ $90457285602$ $6060715747618$ $406067715021534$ $27206534370824038$ $1822837806347587186$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 240 curves (of which all are hyperelliptic):

  • $y^2=17 x^6+23 x^5+6 x^4+57 x^3+47 x^2+15 x+4$
  • $y^2=34 x^6+45 x^5+36 x^4+57 x^3+47 x^2+48 x+17$
  • $y^2=17 x^5+62 x^4+27 x^3+17 x^2+43 x+64$
  • $y^2=18 x^6+66 x^5+63 x^4+36 x^3+43 x^2+6 x+20$
  • $y^2=64 x^6+35 x^5+34 x^4+56 x^3+38 x^2+57 x+22$
  • $y^2=48 x^6+59 x^5+65 x^4+41 x^3+24 x^2+31 x+53$
  • $y^2=47 x^6+37 x^5+59 x^4+32 x^3+55 x^2+55 x+16$
  • $y^2=56 x^6+18 x^5+49 x^4+58 x^3+20 x^2+6 x+39$
  • $y^2=34 x^6+7 x^5+17 x^4+7 x^3+33 x^2+60 x+19$
  • $y^2=58 x^6+49 x^5+18 x^4+61 x^3+38 x^2+56 x+47$
  • $y^2=35 x^6+59 x^5+13 x^4+36 x^3+65 x^2+35 x+38$
  • $y^2=47 x^6+32 x^5+47 x^4+20 x^3+64 x^2+32 x+43$
  • $y^2=34 x^6+42 x^5+36 x^4+37 x^3+44 x^2+38 x+64$
  • $y^2=5 x^6+8 x^5+11 x^4+56 x^3+8 x^2+46 x+23$
  • $y^2=63 x^6+31 x^5+62 x^4+9 x^2+44 x+13$
  • $y^2=12 x^6+8 x^5+15 x^4+62 x^3+20 x^2+64 x+65$
  • $y^2=39 x^6+26 x^5+52 x^4+22 x^3+46 x^2+65 x+18$
  • $y^2=51 x^6+33 x^5+61 x^4+13 x^3+15 x^2+14 x+35$
  • $y^2=27 x^6+28 x^5+66 x^4+x^3+34 x^2+3 x+30$
  • $y^2=24 x^6+15 x^5+30 x^4+4 x^3+66 x^2+38 x+59$
  • and 220 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{67}$.

Endomorphism algebra over $\F_{67}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-202 +2 \sqrt{65}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.67.ac_cs$2$(not in LMFDB)