Invariants
| Base field: | $\F_{41}$ |
| Dimension: | $2$ |
| L-polynomial: | $1 + 43 x^{2} + 1681 x^{4}$ |
| Frobenius angles: | $\pm0.337853343996$, $\pm0.662146656004$ |
| Angle rank: | $1$ (numerical) |
| Number field: | \(\Q(\sqrt{-5}, \sqrt{39})\) |
| Galois group: | $C_2^2$ |
| Jacobians: | $132$ |
| Cyclic group of points: | no |
| Non-cyclic primes: | $5$ |
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
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
|---|---|---|---|---|---|
| $A(\F_{q^r})$ | $1725$ | $2975625$ | $4749966900$ | $7993483925625$ | $13422659396443125$ |
| $r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
|---|---|---|---|---|---|---|---|---|---|---|
| $C(\F_{q^r})$ | $42$ | $1768$ | $68922$ | $2828788$ | $115856202$ | $4749829558$ | $194754273882$ | $7984931953828$ | $327381934393962$ | $13422659482733848$ |
Jacobians and polarizations
This isogeny class is principally polarizable and contains the Jacobians of 132 curves (of which all are hyperelliptic):
- $y^2=39 x^6+30 x^5+32 x^4+9 x^2+6 x+27$
- $y^2=29 x^6+16 x^5+28 x^4+13 x^2+36 x+39$
- $y^2=35 x^6+11 x^5+17 x^4+29 x^3+35 x^2+10 x+37$
- $y^2=5 x^6+25 x^5+20 x^4+10 x^3+5 x^2+19 x+17$
- $y^2=40 x^6+5 x^5+38 x^4+11 x^3+12 x^2+18 x+33$
- $y^2=35 x^6+30 x^5+23 x^4+25 x^3+31 x^2+26 x+34$
- $y^2=24 x^6+10 x^5+37 x^4+26 x^3+x^2+2$
- $y^2=21 x^6+19 x^5+17 x^4+33 x^3+6 x^2+12$
- $y^2=16 x^6+25 x^5+23 x^4+17 x^3+21 x^2+12 x+38$
- $y^2=14 x^6+27 x^5+15 x^4+20 x^3+3 x^2+31 x+23$
- $y^2=34 x^6+40 x^5+20 x^4+9 x^3+6 x^2+23 x+31$
- $y^2=40 x^6+35 x^5+38 x^4+13 x^3+36 x^2+15 x+22$
- $y^2=30 x^6+19 x^5+28 x^4+25 x^3+24 x^2+31 x+10$
- $y^2=16 x^6+32 x^5+4 x^4+27 x^3+21 x^2+22 x+19$
- $y^2=6 x^6+10 x^5+36 x^4+17 x^3+13 x^2+12 x+2$
- $y^2=36 x^6+19 x^5+11 x^4+20 x^3+37 x^2+31 x+12$
- $y^2=15 x^6+37 x^5+14 x^4+36 x^3+11 x^2+11 x+9$
- $y^2=8 x^6+17 x^5+2 x^4+11 x^3+25 x^2+25 x+13$
- $y^2=20 x^6+39 x^5+27 x^4+27 x^3+27 x^2+2 x+31$
- $y^2=38 x^6+29 x^5+39 x^4+39 x^3+39 x^2+12 x+22$
- and 112 more
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{41^{2}}$.
Endomorphism algebra over $\F_{41}$| The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-5}, \sqrt{39})\). |
| The base change of $A$ to $\F_{41^{2}}$ is 1.1681.br 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-195}) \)$)$ |
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 |
|---|---|---|
| 2.41.a_abr | $4$ | (not in LMFDB) |