Properties

Label 2.41.ad_c
Base field $\F_{41}$
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:  $\F_{41}$
Dimension:  $2$
L-polynomial:  $1 - 3 x + 2 x^{2} - 123 x^{3} + 1681 x^{4}$
Frobenius angles:  $\pm0.190998009979$, $\pm0.701287815130$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-318 -6 \sqrt{329}})\)
Galois group:  $D_{4}$
Jacobians:  $56$
Isomorphism classes:  56
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1558$ $2819980$ $4724130208$ $7999719264000$ $13425078262513558$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $39$ $1677$ $68544$ $2830993$ $115877079$ $4750118322$ $194755553199$ $7984922813473$ $327381891225984$ $13422659319167277$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 56 curves (of which all are hyperelliptic):

  • $y^2=11 x^6+27 x^5+15 x^4+29 x^3+20 x^2+30 x+16$
  • $y^2=6 x^6+24 x^5+9 x^4+12 x^3+4 x^2+30 x+12$
  • $y^2=40 x^6+9 x^5+10 x^4+4 x^3+2 x^2+27 x+7$
  • $y^2=15 x^6+6 x^5+40 x^4+7 x^2+22 x+12$
  • $y^2=30 x^6+26 x^5+17 x^4+14 x^3+16 x^2+32 x+28$
  • $y^2=22 x^6+23 x^5+9 x^4+34 x^3+24 x^2+15 x+14$
  • $y^2=34 x^6+33 x^5+30 x^4+35 x^3+28 x^2+9 x+12$
  • $y^2=17 x^6+2 x^5+18 x^4+17 x^3+17 x^2+20 x+29$
  • $y^2=22 x^6+4 x^5+22 x^4+24 x^3+19 x^2+8 x+34$
  • $y^2=32 x^6+29 x^5+26 x^4+15 x^3+16 x+35$
  • $y^2=38 x^6+37 x^5+7 x^4+9 x^3+22 x^2+4 x+21$
  • $y^2=14 x^6+2 x^5+14 x^4+26 x^3+18 x^2+15 x+29$
  • $y^2=33 x^6+19 x^5+18 x^4+11 x^3+29 x^2+34 x+26$
  • $y^2=2 x^6+27 x^5+31 x^4+3 x^3+39 x^2+29 x+14$
  • $y^2=22 x^6+17 x^5+4 x^4+27 x^3+17 x^2+32 x+29$
  • $y^2=29 x^6+31 x^5+24 x^4+15 x^3+4 x^2+37 x+3$
  • $y^2=12 x^6+11 x^5+23 x^4+38 x^2+24 x+22$
  • $y^2=19 x^6+34 x^5+14 x^4+9 x^3+38 x^2+26 x+17$
  • $y^2=23 x^6+17 x^5+11 x^4+14 x^3+12 x+13$
  • $y^2=24 x^6+38 x^5+22 x^4+28 x^3+30 x^2+21 x+40$
  • and 36 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{41}$.

Endomorphism algebra over $\F_{41}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-318 -6 \sqrt{329}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.41.d_c$2$(not in LMFDB)