Properties

Label 4.4.9792.1-17.1-a4
Base field 4.4.9792.1
Conductor norm \( 17 \)
CM no
Base change yes
Q-curve no
Torsion order \( 2 \)
Rank \( 1 \)

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Base field 4.4.9792.1

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

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([7, 2, -7, -2, 1]))
 
Copy content gp:K = nfinit(Polrev([7, 2, -7, -2, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![7, 2, -7, -2, 1]);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(Qx([7, 2, -7, -2, 1]))
 

Weierstrass equation

\({y}^2+\left(-a^{3}+4a^{2}+2a-7\right){x}{y}+{y}={x}^{3}+\left(2a^{3}-7a^{2}-3a+12\right){x}^{2}+\left(-a^{3}+11a^{2}-7a-33\right){x}+10a^{3}-10a^{2}-68a-49\)
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([-7,2,4,-1]),K([12,-3,-7,2]),K([1,0,0,0]),K([-33,-7,11,-1]),K([-49,-68,-10,10])])
 
Copy content gp:E = ellinit([Polrev([-7,2,4,-1]),Polrev([12,-3,-7,2]),Polrev([1,0,0,0]),Polrev([-33,-7,11,-1]),Polrev([-49,-68,-10,10])], K);
 
Copy content magma:E := EllipticCurve([K![-7,2,4,-1],K![12,-3,-7,2],K![1,0,0,0],K![-33,-7,11,-1],K![-49,-68,-10,10]]);
 
Copy content oscar:E = elliptic_curve([K([-7,2,4,-1]),K([12,-3,-7,2]),K([1,0,0,0]),K([-33,-7,11,-1]),K([-49,-68,-10,10])])
 

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

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

Mordell-Weil generators

$P$$\hat{h}(P)$Order
$\left(3 a^{3} - 13 a^{2} - 3 a + 35 : -22 a^{3} + 54 a^{2} + 106 a - 35 : 1\right)$$0.15392115783071432973632055177874505373$$\infty$
$\left(\frac{1}{2} a^{2} - 2 a - 3 : \frac{3}{4} a^{3} - \frac{5}{4} a^{2} - \frac{11}{4} a - \frac{1}{2} : 1\right)$$0$$2$

Invariants

Conductor: $\frak{N}$ = \((a^3-3a^2-2a+3)\) = \((a^3-3a^2-2a+3)\)
Copy content comment:Compute the conductor
 
Copy content sage:E.conductor()
 
Copy content gp:ellglobalred(E)[1]
 
Copy content magma:Conductor(E);
 
Copy content oscar:conductor(E)
 
Conductor norm: $N(\frak{N})$ = \( 17 \) = \(17\)
Copy content comment:Compute the norm of the conductor
 
Copy content sage:E.conductor().norm()
 
Copy content gp:idealnorm(K, ellglobalred(E)[1])
 
Copy content magma:Norm(Conductor(E));
 
Copy content oscar:norm(conductor(E))
 
Discriminant: $\Delta$ = $3a^3-9a^2-9a+11$
Discriminant ideal: $\frak{D}_{\mathrm{min}} = (\Delta)$ = \((3a^3-9a^2-9a+11)\) = \((a^3-3a^2-2a+3)^{2}\)
Copy content comment:Compute the discriminant
 
Copy content sage:E.discriminant()
 
Copy content gp:E.disc
 
Copy content magma:Discriminant(E);
 
Copy content oscar:discriminant(E)
 
Discriminant norm: $N(\frak{D}_{\mathrm{min}}) = N(\Delta)$ = \( 289 \) = \(17^{2}\)
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));
 
Copy content oscar:norm(discriminant(E))
 
j-invariant: $j$ = \( -\frac{3690752}{17} a^{3} + \frac{11072256}{17} a^{2} + \frac{11072256}{17} a - \frac{9475776}{17} \)
Copy content comment:Compute the j-invariant
 
Copy content sage:E.j_invariant()
 
Copy content gp:E.j
 
Copy content magma:jInvariant(E);
 
Copy content oscar:j_invariant(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: $\mathrm{Reg}(E/K)$ \( 0.15392115783071432973632055177874505373 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 0.615684631322857318945282207114980214920 \)
Global period: $\Omega(E/K)$ \( 723.02388680112547613056350617022581572 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 2 \)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(2\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 2.24928900487524 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$$\begin{aligned}2.249289005 \approx L'(E/K,1) & \overset{?}{=} \frac{ \# ะจ(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \\ & \approx \frac{ 1 \cdot 723.023887 \cdot 0.615685 \cdot 2 } { {2^2 \cdot 98.954535} } \\ & \approx 2.249289005 \end{aligned}$$

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 semistable. There is only one prime $\frak{p}$ of bad reduction.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((a^3-3a^2-2a+3)\) \(17\) \(2\) \(I_{2}\) 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
\(2\) 2B
\(3\) 3B.1.2

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2, 3 and 6.
Its isogeny class 17.1-a consists of curves linked by isogenies of degrees dividing 6.

Base change

This elliptic curve is not a \(\Q\)-curve. It is the base change of the following 2 elliptic curves:

Base field Curve
\(\Q(\sqrt{2}) \) 2.2.8.1-289.2-a3
\(\Q(\sqrt{2}) \) 2.2.8.1-1377.2-a3