Properties

Label 1.71.a
Base field $\F_{71}$
Dimension $1$
$p$-rank $0$
Ordinary no
Supersingular yes
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{71}$
Dimension:  $1$
L-polynomial:  $1 + 71 x^{2}$
Frobenius angles:  $\pm0.5$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{-71}) \)
Galois group:  $C_2$
Jacobians:  $14$
Isomorphism classes:  14

This isogeny class is simple and geometrically simple, primitive, not ordinary, and supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is supersingular.

$p$-rank:  $0$
Slopes:  $[1/2, 1/2]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $72$ $5184$ $357912$ $25401600$ $1804229352$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $72$ $5184$ $357912$ $25401600$ $1804229352$ $128100999744$ $9095120158392$ $645753480422400$ $45848500718449032$ $3255243554618339904$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 14 curves (of which 0 are hyperelliptic):

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 \(\Q(\sqrt{-71}) \).
Endomorphism algebra over $\overline{\F}_{71}$
The base change of $A$ to $\F_{71^{2}}$ is the simple isogeny class 1.5041.fm and its endomorphism algebra is the quaternion algebra over \(\Q\) ramified at $71$ and $\infty$.

Base change

This is a primitive isogeny class.

Twists

This isogeny class has no twists.