Properties

Label 2.2.56.1-252.1-b2
Base field \(\Q(\sqrt{14}) \)
Conductor norm \( 252 \)
CM no
Base change yes
Q-curve yes
Torsion order \( 6 \)
Rank \( 1 \)

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Base field \(\Q(\sqrt{14}) \)

Generator \(a\), with minimal polynomial \( x^{2} - 14 \); class number \(1\).

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([-14, 0, 1]))
 
Copy content gp:K = nfinit(Polrev([-14, 0, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-14, 0, 1]);
 

Weierstrass equation

\({y}^2={x}^{3}+{x}^{2}+7{x}\)
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([0,0]),K([1,0]),K([0,0]),K([7,0]),K([0,0])])
 
Copy content gp:E = ellinit([Polrev([0,0]),Polrev([1,0]),Polrev([0,0]),Polrev([7,0]),Polrev([0,0])], K);
 
Copy content magma:E := EllipticCurve([K![0,0],K![1,0],K![0,0],K![7,0],K![0,0]]);
 

This is a global minimal model.

Copy content comment:Test whether it is a global minimal model
 
Copy content sage:E.is_global_minimal_model()
 

Mordell-Weil group structure

\(\Z \oplus \Z/{6}\Z\)

Mordell-Weil generators

$P$$\hat{h}(P)$Order
$\left(\frac{2}{7} : -\frac{19}{49} a : 1\right)$$2.9811696947504565544838345024857085536$$\infty$
$\left(7 : 21 : 1\right)$$0$$6$

Invariants

Conductor: $\frak{N}$ = \((-12a+42)\) = \((-a+4)^{2}\cdot(-2a+7)\cdot(3)\)
Copy content comment:Compute the conductor
 
Copy content sage:E.conductor()
 
Copy content gp:ellglobalred(E)[1]
 
Copy content magma:Conductor(E);
 
Conductor norm: $N(\frak{N})$ = \( 252 \) = \(2^{2}\cdot7\cdot9\)
Copy content comment:Compute the norm of the conductor
 
Copy content sage:E.conductor().norm()
 
Copy content gp:idealnorm(ellglobalred(E)[1])
 
Copy content magma:Norm(Conductor(E));
 
Discriminant: $\Delta$ = $-21168$
Discriminant ideal: $\frak{D}_{\mathrm{min}} = (\Delta)$ = \((-21168)\) = \((-a+4)^{8}\cdot(-2a+7)^{4}\cdot(3)^{3}\)
Copy content comment:Compute the discriminant
 
Copy content sage:E.discriminant()
 
Copy content gp:E.disc
 
Copy content magma:Discriminant(E);
 
Discriminant norm: $N(\frak{D}_{\mathrm{min}}) = N(\Delta)$ = \( 448084224 \) = \(2^{8}\cdot7^{4}\cdot9^{3}\)
Copy content comment:Compute the norm of the discriminant
 
Copy content sage:E.discriminant().norm()
 
Copy content gp:norm(E.disc)
 
Copy content magma:Norm(Discriminant(E));
 
j-invariant: $j$ = \( \frac{2048000}{1323} \)
Copy content comment:Compute the j-invariant
 
Copy content sage:E.j_invariant()
 
Copy content gp:E.j
 
Copy content magma:jInvariant(E);
 
Endomorphism ring: $\mathrm{End}(E)$ = \(\Z\)   
Geometric endomorphism ring: $\mathrm{End}(E_{\overline{\Q}})$ = \(\Z\)    (no potential complex multiplication)
Copy content comment:Test for Complex Multiplication
 
Copy content sage:E.has_cm(), E.cm_discriminant()
 
Copy content magma:HasComplexMultiplication(E);
 
Sato-Tate group: $\mathrm{ST}(E)$ = $\mathrm{SU}(2)$

BSD invariants

Analytic rank: $r_{\mathrm{an}}$= \( 1 \)
Copy content comment:Compute the Mordell-Weil rank
 
Copy content sage:E.rank()
 
Copy content magma:Rank(E);
 
Mordell-Weil rank: $r$ = \(1\)
Regulator: $\mathrm{Reg}(E/K)$ \( 2.9811696947504565544838345024857085536 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 5.9623393895009131089676690049714171072 \)
Global period: $\Omega(E/K)$ \( 4.7974890387035532392272979808542832181 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 36 \)  =  \(3\cdot2^{2}\cdot3\)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(6\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 3.8224047406467204102854146571293412855 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$$\begin{aligned}3.822404741 \approx L'(E/K,1) & \overset{?}{=} \frac{ \# ะจ(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \\ & \approx \frac{ 1 \cdot 4.797489 \cdot 5.962339 \cdot 36 } { {6^2 \cdot 7.483315} } \\ & \approx 3.822404741 \end{aligned}$$

Local data at primes of bad reduction

Copy content comment:Compute the local reduction data at primes of bad reduction
 
Copy content sage:E.local_data()
 
Copy content magma:LocalInformation(E);
 

This elliptic curve is not semistable. There are 3 primes $\frak{p}$ of bad reduction.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((-a+4)\) \(2\) \(3\) \(IV^{*}\) Additive \(-1\) \(2\) \(8\) \(0\)
\((-2a+7)\) \(7\) \(4\) \(I_{4}\) Split multiplicative \(-1\) \(1\) \(4\) \(4\)
\((3)\) \(9\) \(3\) \(I_{3}\) 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
\(3\) 3B.1.1

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2, 3 and 6.
Its isogeny class 252.1-b consists of curves linked by isogenies of degrees dividing 6.

Base change

This elliptic curve is a \(\Q\)-curve. It is the base change of the following 2 elliptic curves:

Base field Curve
\(\Q\) 84.b4
\(\Q\) 9408.r4