Properties

Label 4.4.13888.1-7.2-b2
Base field 4.4.13888.1
Conductor norm \( 7 \)
CM no
Base change no
Q-curve no
Torsion order \( 2 \)
Rank \( 1 \)

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Base field 4.4.13888.1

Generator \(a\), with minimal polynomial \( x^{4} - 2 x^{3} - 7 x^{2} + 6 x + 9 \); class number \(1\).

sage: R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([9, 6, -7, -2, 1]))
 
gp: K = nfinit(Polrev([9, 6, -7, -2, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![9, 6, -7, -2, 1]);
 

Weierstrass equation

\({y}^2+\left(\frac{1}{3}a^{3}-\frac{2}{3}a^{2}-\frac{4}{3}a+1\right){x}{y}+\left(\frac{1}{3}a^{3}-\frac{2}{3}a^{2}-\frac{4}{3}a+2\right){y}={x}^{3}+\left(-\frac{1}{3}a^{3}+\frac{2}{3}a^{2}+\frac{1}{3}a-1\right){x}^{2}+\left(\frac{7}{3}a^{3}+\frac{1}{3}a^{2}-\frac{61}{3}a-19\right){x}-\frac{16}{3}a^{3}+\frac{8}{3}a^{2}+\frac{115}{3}a+27\)
sage: E = EllipticCurve([K([1,-4/3,-2/3,1/3]),K([-1,1/3,2/3,-1/3]),K([2,-4/3,-2/3,1/3]),K([-19,-61/3,1/3,7/3]),K([27,115/3,8/3,-16/3])])
 
gp: E = ellinit([Polrev([1,-4/3,-2/3,1/3]),Polrev([-1,1/3,2/3,-1/3]),Polrev([2,-4/3,-2/3,1/3]),Polrev([-19,-61/3,1/3,7/3]),Polrev([27,115/3,8/3,-16/3])], K);
 
magma: E := EllipticCurve([K![1,-4/3,-2/3,1/3],K![-1,1/3,2/3,-1/3],K![2,-4/3,-2/3,1/3],K![-19,-61/3,1/3,7/3],K![27,115/3,8/3,-16/3]]);
 

This is a global minimal model.

sage: E.is_global_minimal_model()
 

Invariants

Conductor: \((1/3a^3+1/3a^2-1/3a-1)\) = \((1/3a^3+1/3a^2-1/3a-1)\)
sage: E.conductor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
Conductor norm: \( 7 \) = \(7\)
sage: E.conductor().norm()
 
gp: idealnorm(ellglobalred(E)[1])
 
magma: Norm(Conductor(E));
 
Discriminant: \((4/3a^3-5/3a^2-28/3a-4)\) = \((1/3a^3+1/3a^2-1/3a-1)^{3}\)
sage: E.discriminant()
 
gp: E.disc
 
magma: Discriminant(E);
 
Discriminant norm: \( -343 \) = \(-7^{3}\)
sage: E.discriminant().norm()
 
gp: norm(E.disc)
 
magma: Norm(Discriminant(E));
 
j-invariant: \( -\frac{7848998400}{49} a^{3} + \frac{4430760448}{7} a^{2} - \frac{797645568}{7} a - \frac{36197779648}{49} \)
sage: E.j_invariant()
 
gp: E.j
 
magma: jInvariant(E);
 
Endomorphism ring: \(\Z\)
Geometric endomorphism ring: \(\Z\) (no potential complex multiplication)
sage: E.has_cm(), E.cm_discriminant()
 
magma: HasComplexMultiplication(E);
 
Sato-Tate group: $\mathrm{SU}(2)$

Mordell-Weil group

Rank: \(1\)
Generator $\left(-\frac{1}{3} a^{3} + \frac{2}{3} a^{2} + \frac{7}{3} a + 1 : -\frac{2}{3} a^{3} + \frac{4}{3} a^{2} + \frac{5}{3} a - 1 : 1\right)$
Height \(0.47881605862038052750581055982624926738\)
Torsion structure: \(\Z/2\Z\)
sage: T = E.torsion_subgroup(); T.invariants()
 
gp: T = elltors(E); T[2]
 
magma: T,piT := TorsionSubgroup(E); Invariants(T);
 
Torsion generator: $\left(a + \frac{1}{2} : -\frac{1}{4} a^{3} + \frac{3}{2} a + \frac{1}{4} : 1\right)$
sage: T.gens()
 
gp: T[3]
 
magma: [piT(P) : P in Generators(T)];
 

BSD invariants

Analytic rank: \( 1 \)
sage: E.rank()
 
magma: Rank(E);
 
Mordell-Weil rank: \(1\)
Regulator: \( 0.47881605862038052750581055982624926738 \)
Period: \( 222.04088812848876321320285606048320745 \)
Tamagawa product: \( 3 \)
Torsion order: \(2\)
Leading coefficient: \( 2.70646904345154 \)
Analytic order of Ш: \( 1 \) (rounded)

Local data at primes of bad reduction

sage: E.local_data()
 
magma: LocalInformation(E);
 
prime Norm Tamagawa number Kodaira symbol Reduction type Root number ord(\(\mathfrak{N}\)) ord(\(\mathfrak{D}\)) ord\((j)_{-}\)
\((1/3a^3+1/3a^2-1/3a-1)\) \(7\) \(3\) \(I_{3}\) Split multiplicative \(-1\) \(1\) \(3\) \(3\)

Galois Representations

The mod \( p \) Galois Representation has maximal image for all primes \( p < 1000 \) except those listed.

prime Image of Galois Representation
\(2\) 2B
\(3\) 3Ns

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2.
Its isogeny class 7.2-b consists of curves linked by isogenies of degree 2.

Base change

This elliptic curve is not a \(\Q\)-curve.

It is not the base change of an elliptic curve defined over any subfield.