# Properties

 Label 20449.a3 Conductor 20449 Discriminant -94060852367339 j-invariant $$-\frac{4096}{11}$$ CM no Rank 2 Torsion Structure $$\mathrm{Trivial}$$

# Related objects

Show commands for: Magma / SageMath / Pari/GP

## Minimal Weierstrass equation

magma: E := EllipticCurve([0, -1, 1, -6816, -512172]); // or

magma: E := EllipticCurve("20449g1");

sage: E = EllipticCurve([0, -1, 1, -6816, -512172]) # or

sage: E = EllipticCurve("20449g1")

gp: E = ellinit([0, -1, 1, -6816, -512172]) \\ or

gp: E = ellinit("20449g1")

$$y^2 + y = x^{3} - x^{2} - 6816 x - 512172$$

## Mordell-Weil group structure

$$\Z^2$$

### Infinite order Mordell-Weil generators and heights

magma: Generators(E);

sage: E.gens()

 $$P$$ = $$\left(114, 423\right)$$ $$\left(139, 1098\right)$$ $$\hat{h}(P)$$ ≈ 2.15662575723 2.72216543658

## Integral points

magma: IntegralPoints(E);

sage: E.integral_points()

$$\left(114, 423\right)$$, $$\left(114, -424\right)$$, $$\left(136, 1028\right)$$, $$\left(136, -1029\right)$$, $$\left(139, 1098\right)$$, $$\left(139, -1099\right)$$, $$\left(477, 10224\right)$$, $$\left(477, -10225\right)$$, $$\left(4107, 263114\right)$$, $$\left(4107, -263115\right)$$, $$\left(502407, 356109110\right)$$, $$\left(502407, -356109111\right)$$

## Invariants

 magma: Conductor(E);  sage: E.conductor().factor()  gp: ellglobalred(E)[1] Conductor: $$20449$$ = $$11^{2} \cdot 13^{2}$$ magma: Discriminant(E);  sage: E.discriminant().factor()  gp: E.disc Discriminant: $$-94060852367339$$ = $$-1 \cdot 11^{7} \cdot 13^{6}$$ magma: jInvariant(E);  sage: E.j_invariant().factor()  gp: E.j j-invariant: $$-\frac{4096}{11}$$ = $$-1 \cdot 2^{12} \cdot 11^{-1}$$ Endomorphism ring: $$\Z$$ (no Complex Multiplication) Sato-Tate Group: $\mathrm{SU}(2)$

## BSD invariants

 magma: Rank(E);  sage: E.rank() Rank: $$2$$ magma: Regulator(E);  sage: E.regulator() Regulator: $$1.54375176698$$ magma: RealPeriod(E);  sage: E.period_lattice().omega()  gp: E.omega[1] Real period: $$0.243984747996$$ magma: TamagawaNumbers(E);  sage: E.tamagawa_numbers()  gp: gr=ellglobalred(E); [[gr[4][i,1],gr[5][i][4]] | i<-[1..#gr[4][,1]]] Tamagawa product: $$8$$  = $$2^{2}\cdot2$$ magma: Order(TorsionSubgroup(E));  sage: E.torsion_order()  gp: elltors(E)[1] Torsion order: $$1$$ magma: MordellWeilShaInformation(E);  sage: E.sha().an_numerical() Analytic order of Ш: $$1$$ (rounded)

## Modular invariants

#### Modular form 20449.2.a.a

magma: ModularForm(E);

sage: E.q_eigenform(20)

gp: xy = elltaniyama(E);

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

$$q - 2q^{2} - q^{3} + 2q^{4} - q^{5} + 2q^{6} - 2q^{7} - 2q^{9} + 2q^{10} - 2q^{12} + 4q^{14} + q^{15} - 4q^{16} + 2q^{17} + 4q^{18} + O(q^{20})$$

For more coefficients, see the Downloads section to the right.

 magma: ModularDegree(E);  sage: E.modular_degree() Modular degree: 51840 $$\Gamma_0(N)$$-optimal: yes Manin constant: 1

#### Special L-value

magma: Lr1 where r,Lr1 := AnalyticRank(E: Precision:=12);

sage: r = E.rank();

sage: E.lseries().dokchitser().derivative(1,r)/r.factorial()

gp: ar = ellanalyticrank(E);

gp: ar[2]/factorial(ar[1])

$$L^{(2)}(E,1)/2!$$ ≈ $$3.01321508667$$

## Local data

This elliptic curve is not semistable.

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

sage: E.local_data()

gp: ellglobalred(E)[5]

prime Tamagawa number Kodaira symbol Reduction type Root number ord($$N$$) ord($$\Delta$$) ord$$(j)_{-}$$
$$11$$ $$4$$ $$I_1^{*}$$ Additive -1 2 7 1
$$13$$ $$2$$ $$I_0^{*}$$ Additive 1 2 6 0

## Galois representations

The 2-adic representation attached to this elliptic curve is surjective.

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

sage: rho = E.galois_representation();

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

The mod $$p$$ Galois representation has maximal image $$\GL(2,\F_p)$$ for all primes $$p$$ except those listed.

prime Image of Galois representation
$$5$$ B.4.1

## $p$-adic data

### $p$-adic regulators

sage: [E.padic_regulator(p) for p in primes(3,20) if E.conductor().valuation(p)<2]

Note: $$p$$-adic regulator data only exists for primes $$p\ge5$$ of good ordinary reduction.

## 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 ss ordinary ordinary ordinary add add ordinary ss ordinary ss ordinary ordinary ordinary ordinary ordinary ? 2 2 2 - - 2 2,2 2 2,2 2 2 2 2 2 ? 0 0 0 - - 0 0,0 0 0,0 0 0 0 0 0

An entry ? indicates that the invariants have not yet been computed.

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 $$d=$$ 5 and 25.
Its isogeny class 20449.a consists of 3 curves linked by isogenies of degrees dividing 25.

## Growth of torsion in number fields

The number fields $K$ of degree up to 7 such that $E(K)_{\rm tors}$ is strictly larger than $E(\Q)_{\rm tors}$ (which is trivial) are as follows:

$[K:\Q]$ $K$ $E(K)_{\rm tors}$ Base-change curve
2 $$\Q(\sqrt{-143})$$ $$\Z/5\Z$$ Not in database
3 3.1.44.1 $$\Z/2\Z$$ Not in database
6 6.0.21296.1 $$\Z/2\Z \times \Z/2\Z$$ Not in database
6.0.46787312.1 $$\Z/10\Z$$ Not in database

We only show fields where the torsion growth is primitive. For each field $K$ we either show its label, or a defining polynomial when $K$ is not in the database.