Properties

Label 4.4.2000.1-320.1-h4
Base field \(\Q(\zeta_{20})^+\)
Conductor norm \( 320 \)
CM no
Base change yes
Q-curve yes
Torsion order \( 8 \)
Rank \( 1 \)

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Base field \(\Q(\zeta_{20})^+\)

Generator \(a\), with minimal polynomial \( x^{4} - 5 x^{2} + 5 \); class number \(1\).

sage: R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([5, 0, -5, 0, 1]))
 
gp: K = nfinit(Polrev([5, 0, -5, 0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![5, 0, -5, 0, 1]);
 

Weierstrass equation

\({y}^2+\left(a^{2}+a-3\right){x}{y}+\left(a^{3}+a^{2}-3a-2\right){y}={x}^{3}+\left(a^{3}-3a-1\right){x}^{2}+\left(7a^{3}-22a-10\right){x}-17a^{3}-8a^{2}+52a+45\)
sage: E = EllipticCurve([K([-3,1,1,0]),K([-1,-3,0,1]),K([-2,-3,1,1]),K([-10,-22,0,7]),K([45,52,-8,-17])])
 
gp: E = ellinit([Polrev([-3,1,1,0]),Polrev([-1,-3,0,1]),Polrev([-2,-3,1,1]),Polrev([-10,-22,0,7]),Polrev([45,52,-8,-17])], K);
 
magma: E := EllipticCurve([K![-3,1,1,0],K![-1,-3,0,1],K![-2,-3,1,1],K![-10,-22,0,7],K![45,52,-8,-17]]);
 

This is a global minimal model.

sage: E.is_global_minimal_model()
 

Invariants

Conductor: \((-2a^2-2a+10)\) = \((a^3-a^2-3a+2)^{3}\cdot(a)\)
sage: E.conductor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
Conductor norm: \( 320 \) = \(4^{3}\cdot5\)
sage: E.conductor().norm()
 
gp: idealnorm(ellglobalred(E)[1])
 
magma: Norm(Conductor(E));
 
Discriminant: \((100)\) = \((a^3-a^2-3a+2)^{4}\cdot(a)^{8}\)
sage: E.discriminant()
 
gp: E.disc
 
magma: Discriminant(E);
 
Discriminant norm: \( 100000000 \) = \(4^{4}\cdot5^{8}\)
sage: E.discriminant().norm()
 
gp: norm(E.disc)
 
magma: Norm(Discriminant(E));
 
j-invariant: \( \frac{148176}{25} \)
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 $\left(-4 a^{3} - 3 a^{2} + 13 a + 12 : 10 a^{3} + 13 a^{2} - 36 a - 46 : 1\right)$
Height \(0.11667418787495715546330228574753011216\)
Torsion structure: \(\Z/2\Z\oplus\Z/4\Z\)
sage: T = E.torsion_subgroup(); T.invariants()
 
gp: T = elltors(E); T[2]
 
magma: T,piT := TorsionSubgroup(E); Invariants(T);
 
Torsion generators: $\left(-a^{3} + 3 a + 1 : -a^{3} + 3 a : 1\right)$ $\left(-a^{3} + 2 a^{2} + 2 a - 3 : -a^{3} - 4 a^{2} + 6 a + 9 : 1\right)$
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: \( 0.11667418787495715546330228574753011216 \)
Period: \( 1063.2715998608255672776290799001948161 \)
Tamagawa product: \( 16 \)  =  \(2\cdot2^{3}\)
Torsion order: \(8\)
Leading coefficient: \( 2.77398432544477 \)
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\((j)_{-}\)
\((a^3-a^2-3a+2)\) \(4\) \(2\) \(III\) Additive \(1\) \(3\) \(4\) \(0\)
\((a)\) \(5\) \(8\) \(I_{8}\) Split multiplicative \(-1\) \(1\) \(8\) \(8\)

Galois Representations

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

prime Image of Galois Representation
\(2\) 2Cs

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2 and 4.
Its isogeny class 320.1-h consists of curves linked by isogenies of degrees dividing 16.

Base change

This elliptic curve is a \(\Q\)-curve. It is the base change of the following 4 elliptic curves:

Base field Curve
\(\Q\) 80.a2
\(\Q\) 400.e2
\(\Q(\sqrt{5}) \) 2.2.5.1-1280.1-i4
\(\Q(\sqrt{5}) \) 2.2.5.1-1600.1-a4