# Properties

 Label 26520i3 Conductor $26520$ Discriminant $-2.971\times 10^{16}$ j-invariant $$\frac{900753985478876}{29018422265625}$$ CM no Rank $1$ Torsion structure $$\Z/{4}\Z$$

# Related objects

Show commands: Magma / Pari/GP / SageMath

## Minimal Weierstrass equation

sage: E = EllipticCurve([0, 1, 0, 20280, 8225568])

gp: E = ellinit([0, 1, 0, 20280, 8225568])

magma: E := EllipticCurve([0, 1, 0, 20280, 8225568]);

$$y^2=x^3+x^2+20280x+8225568$$

## Mordell-Weil group structure

$\Z\times \Z/{4}\Z$

### Infinite order Mordell-Weil generator and height

sage: E.gens()

magma: Generators(E);

 $P$ = $$\left(-69, 2550\right)$$ $\hat{h}(P)$ ≈ $1.3807356878625789568637797914$

## Torsion generators

sage: E.torsion_subgroup().gens()

gp: elltors(E)

magma: TorsionSubgroup(E);

$$\left(156, 3900\right)$$

## Integral points

sage: E.integral_points()

magma: IntegralPoints(E);

$$\left(-169, 0\right)$$, $$(-69,\pm 2550)$$, $$(-52,\pm 2652)$$, $$(156,\pm 3900)$$, $$(93756,\pm 28707900)$$

## Invariants

 sage: E.conductor().factor()  gp: ellglobalred(E)[1]  magma: Conductor(E); Conductor: $$26520$$ = $2^{3} \cdot 3 \cdot 5 \cdot 13 \cdot 17$ sage: E.discriminant().factor()  gp: E.disc  magma: Discriminant(E); Discriminant: $-29714864400000000$ = $-1 \cdot 2^{10} \cdot 3^{2} \cdot 5^{8} \cdot 13^{4} \cdot 17^{2}$ sage: E.j_invariant().factor()  gp: E.j  magma: jInvariant(E); j-invariant: $$\frac{900753985478876}{29018422265625}$$ = $2^{2} \cdot 3^{-2} \cdot 5^{-8} \cdot 13^{-4} \cdot 17^{-2} \cdot 83^{3} \cdot 733^{3}$ Endomorphism ring: $\Z$ Geometric endomorphism ring: $$\Z$$ (no potential complex multiplication) Sato-Tate group: $\mathrm{SU}(2)$ Faltings height: $1.8408571735850390857544959117\dots$ Stable Faltings height: $1.2632345231184179945734691438\dots$

## BSD invariants

 sage: E.rank()  magma: Rank(E); Analytic rank: $1$ sage: E.regulator()  magma: Regulator(E); Regulator: $1.3807356878625789568637797914\dots$ sage: E.period_lattice().omega()  gp: E.omega[1]  magma: RealPeriod(E); Real period: $0.28068597701241204802659074826\dots$ sage: E.tamagawa_numbers()  gp: gr=ellglobalred(E); [[gr[4][i,1],gr[5][i][4]] | i<-[1..#gr[4][,1]]]  magma: TamagawaNumbers(E); Tamagawa product: $256$  = $2\cdot2\cdot2^{3}\cdot2^{2}\cdot2$ sage: E.torsion_order()  gp: elltors(E)[1]  magma: Order(TorsionSubgroup(E)); Torsion order: $4$ sage: E.sha().an_numerical()  magma: MordellWeilShaInformation(E); Analytic order of Ш: $1$ (exact) sage: r = E.rank(); sage: E.lseries().dokchitser().derivative(1,r)/r.factorial()  gp: ar = ellanalyticrank(E); gp: ar[2]/factorial(ar[1])  magma: Lr1 where r,Lr1 := AnalyticRank(E: Precision:=12); Special value: $L'(E,1)$ ≈ $6.2008503286978043826676644666504583691$

## Modular invariants

Modular form 26520.2.a.ba

sage: E.q_eigenform(20)

gp: xy = elltaniyama(E);

gp: x*deriv(xy[1])/(2*xy[2]+E.a1*xy[1]+E.a3)

magma: ModularForm(E);

$$q + q^{3} + q^{5} - 4q^{7} + q^{9} + q^{13} + q^{15} + q^{17} + O(q^{20})$$

 sage: E.modular_degree()  magma: ModularDegree(E); Modular degree: 196608 $\Gamma_0(N)$-optimal: no Manin constant: 1

## Local data

This elliptic curve is not semistable. There are 5 primes of bad reduction:

sage: E.local_data()

gp: ellglobalred(E)[5]

magma: [LocalInformation(E,p) : p in BadPrimes(E)];

prime Tamagawa number Kodaira symbol Reduction type Root number ord($N$) ord($\Delta$) ord$(j)_{-}$
$2$ $2$ $III^{*}$ Additive 1 3 10 0
$3$ $2$ $I_{2}$ Split multiplicative -1 1 2 2
$5$ $8$ $I_{8}$ Split multiplicative -1 1 8 8
$13$ $4$ $I_{4}$ Split multiplicative -1 1 4 4
$17$ $2$ $I_{2}$ Split multiplicative -1 1 2 2

## Galois representations

sage: rho = E.galois_representation();

sage: [rho.image_type(p) for p in rho.non_surjective()]

magma: [GaloisRepresentation(E,p): p in PrimesUpTo(20)];

The $\ell$-adic Galois representation has maximal image for all primes $\ell$ except those listed in the table below.

prime $\ell$ mod-$\ell$ image $\ell$-adic image
$2$ 2B 4.24.0.11

## $p$-adic regulators

sage: [E.padic_regulator(p) for p in primes(5,20) if E.conductor().valuation(p)<2]

$p$-adic regulators are not yet computed for curves that are not $\Gamma_0$-optimal.

## Iwasawa invariants

 $p$ Reduction type $\lambda$-invariant(s) $\mu$-invariant(s) 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 add split split ordinary ss split split ss ss ordinary ordinary ordinary ordinary ordinary ordinary - 2 2 1 1,1 2 2 1,1 1,1 1 1 1 1 1 1 - 0 0 0 0,0 0 0 0,0 0,0 0 0 0 0 0 0

An entry - indicates that the invariants are not computed because the reduction is additive.

## Isogenies

This curve has non-trivial cyclic isogenies of degree $d$ for $d=$ 2 and 4.
Its isogeny class 26520i consists of 3 curves linked by isogenies of degrees dividing 4.

## Growth of torsion in number fields

The number fields $K$ of degree less than 24 such that $E(K)_{\rm tors}$ is strictly larger than $E(\Q)_{\rm tors}$ $\cong \Z/{4}\Z$ are as follows:

 $[K:\Q]$ $E(K)_{\rm tors}$ Base change curve $K$ $2$ $$\Q(\sqrt{-1})$$ $$\Z/2\Z \times \Z/4\Z$$ Not in database $4$ $$\Q(i, \sqrt{51})$$ $$\Z/4\Z \times \Z/4\Z$$ Not in database $4$ 4.2.97344.2 $$\Z/8\Z$$ Not in database $8$ 8.0.156332410863616.72 $$\Z/2\Z \times \Z/8\Z$$ Not in database $8$ 8.0.151613669376.14 $$\Z/2\Z \times \Z/8\Z$$ Not in database $8$ Deg 8 $$\Z/12\Z$$ Not in database $16$ Deg 16 $$\Z/4\Z \times \Z/8\Z$$ Not in database $16$ Deg 16 $$\Z/4\Z \times \Z/8\Z$$ Not in database $16$ Deg 16 $$\Z/16\Z$$ Not in database $16$ Deg 16 $$\Z/2\Z \times \Z/12\Z$$ Not in database

We only show fields where the torsion growth is primitive. For fields not in the database, click on the degree shown to reveal the defining polynomial.