Abelian variety isogeny class 1.491.as over $\F_{491}$

• Label: 1.491.as
• Base field: $\F_{491}$
• Dimension: $1$
• $p$-rank: $1$
• Ordinary: yes
• Supersingular: no
• Simple: yes
• Geometrically simple: yes
• Primitive: yes
• Principally polarizable: yes
• Contains a Jacobian: yes

Invariants

Base field:	$\F_{491}$
Dimension:	$1$
L-polynomial:	$1 - 18 x + 491 x^{2}$
Frobenius angles:	$\pm0.366866057469$
Angle rank:	$1$ (numerical)
Number field:	\(\Q(\sqrt{-410}) \)
Galois group:	$C_2$
Jacobians:	$16$

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:	$1$
Slopes:	$[0, 1]$

Point counts

Point counts of the abelian variety

$r$	$1$	$2$	$3$	$4$	$5$
$A(\F_{q^r})$	$474$	$241740$	$118391454$	$58120097760$	$28536934574154$

Point counts of the curve

$r$	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$	$9$	$10$
$C(\F_{q^r})$	$474$	$241740$	$118391454$	$58120097760$	$28536934574154$	$14011639236130860$	$6879714959836171374$	$3377940044846817824640$	$1658568561965404293621114$	$814357163924247085997863500$

Jacobians and polarizations

This isogeny class contains the Jacobians of 16 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{491}$.

Endomorphism algebra over $\F_{491}$

The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-410}) \).

Base change

This is a primitive isogeny class.

Twists

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

Twist	Extension degree	Common base change
1.491.s	$2$	(not in LMFDB)