Properties

Label 2.0.7.1-30492.5-r3
Base field \(\Q(\sqrt{-7}) \)
Conductor norm \( 30492 \)
CM no
Base change yes
Q-curve yes
Torsion order \( 4 \)
Rank \( 1 \)

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Base field \(\Q(\sqrt{-7}) \)

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

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

Weierstrass equation

\({y}^2+{x}{y}+{y}={x}^{3}+{x}^{2}-405{x}+4731\)
sage: E = EllipticCurve([K([1,0]),K([1,0]),K([1,0]),K([-405,0]),K([4731,0])])
 
gp: E = ellinit([Polrev([1,0]),Polrev([1,0]),Polrev([1,0]),Polrev([-405,0]),Polrev([4731,0])], K);
 
magma: E := EllipticCurve([K![1,0],K![1,0],K![1,0],K![-405,0],K![4731,0]]);
 

This is a global minimal model.

sage: E.is_global_minimal_model()
 

Mordell-Weil group structure

\(\Z \oplus \Z/{2}\Z \oplus \Z/{2}\Z\)

Mordell-Weil generators

$P$$\hat{h}(P)$Order
$\left(8 a + 7 : 32 a - 36 : 1\right)$$0.039411059881924719147375335478563588291$$\infty$
$\left(-25 : 12 : 1\right)$$0$$2$
$\left(-\frac{21}{4} a + \frac{29}{2} : \frac{21}{8} a - \frac{31}{4} : 1\right)$$0$$2$

Invariants

Conductor: $\frak{N}$ = \((-132a+66)\) = \((a)\cdot(-a+1)\cdot(-2a+1)\cdot(3)\cdot(-2a+3)\cdot(2a+1)\)
sage: E.conductor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
Conductor norm: $N(\frak{N})$ = \( 30492 \) = \(2\cdot2\cdot7\cdot9\cdot11\cdot11\)
sage: E.conductor().norm()
 
gp: idealnorm(ellglobalred(E)[1])
 
magma: Norm(Conductor(E));
 
Discriminant: $\Delta$ = $-6119866368$
Discriminant ideal: $\frak{D}_{\mathrm{min}} = (\Delta)$ = \((-6119866368)\) = \((a)^{14}\cdot(-a+1)^{14}\cdot(-2a+1)^{6}\cdot(3)^{2}\cdot(-2a+3)^{2}\cdot(2a+1)^{2}\)
sage: E.discriminant()
 
gp: E.disc
 
magma: Discriminant(E);
 
Discriminant norm: $N(\frak{D}_{\mathrm{min}}) = N(\Delta)$ = \( 37452764362177511424 \) = \(2^{14}\cdot2^{14}\cdot7^{6}\cdot9^{2}\cdot11^{2}\cdot11^{2}\)
sage: E.discriminant().norm()
 
gp: norm(E.disc)
 
magma: Norm(Discriminant(E));
 
j-invariant: $j$ = \( -\frac{7347774183121}{6119866368} \)
sage: E.j_invariant()
 
gp: E.j
 
magma: jInvariant(E);
 
Endomorphism ring: $\mathrm{End}(E)$ = \(\Z\)   
Geometric endomorphism ring: $\mathrm{End}(E_{\overline{\Q}})$ = \(\Z\)    (no potential complex multiplication)
sage: E.has_cm(), E.cm_discriminant()
 
magma: HasComplexMultiplication(E);
 
Sato-Tate group: $\mathrm{ST}(E)$ = $\mathrm{SU}(2)$

BSD invariants

Analytic rank: $r_{\mathrm{an}}$= \( 1 \)
sage: E.rank()
 
magma: Rank(E);
 
Mordell-Weil rank: $r$ = \(1\)
Regulator: $\mathrm{Reg}(E/K)$ \( 0.039411059881924719147375335478563588291 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 0.07882211976384943829475067095712717658200 \)
Global period: $\Omega(E/K)$ \( 0.632315149937639138588724479963902252800 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 9408 \)  =  \(( 2 \cdot 7 )\cdot( 2 \cdot 7 )\cdot( 2 \cdot 3 )\cdot2\cdot2\cdot2\)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(4\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 11.076690056940344868883761426125615045 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$\displaystyle 11.076690057 \approx L'(E/K,1) \overset{?}{=} \frac{ \# Ш(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \approx \frac{ 1 \cdot 0.632315 \cdot 0.078822 \cdot 9408 } { {4^2 \cdot 2.645751} } \approx 11.076690057$

Local data at primes of bad reduction

sage: E.local_data()
 
magma: LocalInformation(E);
 

This elliptic curve is semistable. There are 6 primes $\frak{p}$ of bad reduction.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((a)\) \(2\) \(14\) \(I_{14}\) Split multiplicative \(-1\) \(1\) \(14\) \(14\)
\((-a+1)\) \(2\) \(14\) \(I_{14}\) Split multiplicative \(-1\) \(1\) \(14\) \(14\)
\((-2a+1)\) \(7\) \(6\) \(I_{6}\) Split multiplicative \(-1\) \(1\) \(6\) \(6\)
\((3)\) \(9\) \(2\) \(I_{2}\) Split multiplicative \(-1\) \(1\) \(2\) \(2\)
\((-2a+3)\) \(11\) \(2\) \(I_{2}\) Non-split multiplicative \(1\) \(1\) \(2\) \(2\)
\((2a+1)\) \(11\) \(2\) \(I_{2}\) Non-split multiplicative \(1\) \(1\) \(2\) \(2\)

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.
Its isogeny class 30492.5-r consists of curves linked by isogenies of degrees dividing 4.

Base change

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

Base field Curve
\(\Q\) 462.e2
\(\Q\) 3234.v2