Properties

Label 2.71.a_adg
Base field $\F_{71}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 - 84 x^{2} + 5041 x^{4}$
Frobenius angles:  $\pm0.149258255063$, $\pm0.850741744937$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-58}, \sqrt{226})\)
Galois group:  $C_2^2$
Jacobians:  $14$
Cyclic group of points:    yes

This isogeny class is simple but not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4958$ $24581764$ $128100961550$ $645907382725264$ $3255243551093960078$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $72$ $4874$ $357912$ $25417734$ $1804229352$ $128101639178$ $9095120158392$ $645753614579134$ $45848500718449032$ $3255243551178038954$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 14 curves (of which all are hyperelliptic):

  • $y^2=52 x^6+31 x^5+43 x^4+45 x^3+16 x^2+29 x+64$
  • $y^2=9 x^6+4 x^5+17 x^4+31 x^3+41 x^2+61 x+22$
  • $y^2=44 x^6+23 x^5+45 x^4+x^3+38 x^2+32 x+20$
  • $y^2=24 x^6+19 x^5+31 x^4+7 x^3+53 x^2+11 x+69$
  • $y^2=56 x^6+55 x^5+55 x^4+2 x^3+64 x^2+28 x+23$
  • $y^2=37 x^6+30 x^5+30 x^4+14 x^3+22 x^2+54 x+19$
  • $y^2=47 x^6+47 x^5+50 x^4+9 x^3+4 x^2+66 x+49$
  • $y^2=45 x^6+45 x^5+66 x^4+63 x^3+28 x^2+36 x+59$
  • $y^2=55 x^6+66 x^5+12 x^4+31 x^3+30 x^2+57 x+22$
  • $y^2=30 x^6+36 x^5+13 x^4+4 x^3+68 x^2+44 x+12$
  • $y^2=68 x^6+4 x^5+66 x^4+57 x^3+3 x^2+34 x+36$
  • $y^2=50 x^6+28 x^5+36 x^4+44 x^3+21 x^2+25 x+39$
  • $y^2=55 x^6+39 x^5+15 x^4+58 x^3+22 x^2+45$
  • $y^2=30 x^6+60 x^5+34 x^4+51 x^3+12 x^2+31$

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{71^{2}}$.

Endomorphism algebra over $\F_{71}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-58}, \sqrt{226})\).
Endomorphism algebra over $\overline{\F}_{71}$
The base change of $A$ to $\F_{71^{2}}$ is 1.5041.adg 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-3277}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.71.a_dg$4$(not in LMFDB)