Properties

Label 2.2.17.1-144.4-d3
Base field Q(17)\Q(\sqrt{17})
Conductor norm 144 144
CM no
Base change no
Q-curve no
Torsion order 2 2
Rank 1 1

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Base field Q(17)\Q(\sqrt{17})

Generator aa, with minimal polynomial x2x4 x^{2} - x - 4 ; class number 11.

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([-4, -1, 1]))
 
Copy content gp:K = nfinit(Polrev([-4, -1, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-4, -1, 1]);
 

Weierstrass equation

y2+axy=x3+x2+(6a8)x+5a+8{y}^2+a{x}{y}={x}^{3}+{x}^{2}+\left(-6a-8\right){x}+5a+8
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([0,1]),K([1,0]),K([0,0]),K([-8,-6]),K([8,5])])
 
Copy content gp:E = ellinit([Polrev([0,1]),Polrev([1,0]),Polrev([0,0]),Polrev([-8,-6]),Polrev([8,5])], K);
 
Copy content magma:E := EllipticCurve([K![0,1],K![1,0],K![0,0],K![-8,-6],K![8,5]]);
 

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

ZZ/2Z\Z \oplus \Z/{2}\Z

Mordell-Weil generators

PPh^(P)\hat{h}(P)Order
(0:a+2:1)\left(0 : a + 2 : 1\right)0.458834123819697926412651258709724620920.45883412381969792641265125870972462092\infty
(34a+1:78a32:1)\left(\frac{3}{4} a + 1 : -\frac{7}{8} a - \frac{3}{2} : 1\right)0022

Invariants

Conductor: N\frak{N} = (3a+12)(3a+12) = (a+2)4(3)(-a+2)^{4}\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(N)N(\frak{N}) = 144 144 = 2492^{4}\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: Δ\Delta = 1599a+3961599a+396
Discriminant ideal: Dmin=(Δ)\frak{D}_{\mathrm{min}} = (\Delta) = (1599a+396)(1599a+396) = (a+2)20(3)(-a+2)^{20}\cdot(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(Dmin)=N(Δ)N(\frak{D}_{\mathrm{min}}) = N(\Delta) = 9437184 -9437184 = 2209-2^{20}\cdot9
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: jj = 1095125768a+2055079768 \frac{1095125}{768} a + \frac{2055079}{768}
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: End(E)\mathrm{End}(E) = Z\Z   
Geometric endomorphism ring: End(EQ)\mathrm{End}(E_{\overline{\Q}}) = Z\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: ST(E)\mathrm{ST}(E) = SU(2)\mathrm{SU}(2)

BSD invariants

Analytic rank: ranr_{\mathrm{an}}= 1 1
Copy content comment:Compute the Mordell-Weil rank
 
Copy content sage:E.rank()
 
Copy content magma:Rank(E);
 
Mordell-Weil rank: rr = 11
Regulator: Reg(E/K)\mathrm{Reg}(E/K) 0.45883412381969792641265125870972462092 0.45883412381969792641265125870972462092
Néron-Tate Regulator: RegNT(E/K)\mathrm{Reg}_{\mathrm{NT}}(E/K) 0.917668247639395852825302517419449241840 0.917668247639395852825302517419449241840
Global period: Ω(E/K)\Omega(E/K) 10.041230522034847068511366620133570423 10.041230522034847068511366620133570423
Tamagawa product: pcp\prod_{\frak{p}}c_{\frak{p}}= 4 4  =  2212^{2}\cdot1
Torsion order: #E(K)tor\#E(K)_{\mathrm{tor}}= 22
Special value: L(r)(E/K,1)/r!L^{(r)}(E/K,1)/r! 2.2348489837483986559902860541349287202 2.2348489837483986559902860541349287202
Analytic order of Ш: Шan{}_{\mathrm{an}}= 1 1 (rounded)

BSD formula

2.234848984L(E/K,1)=?#Ш(E/K)Ω(E/K)RegNT(E/K)pcp#E(K)tor2dK1/2110.0412310.9176684224.1231062.234848984\begin{aligned}2.234848984 \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 10.041231 \cdot 0.917668 \cdot 4 } { {2^2 \cdot 4.123106} } \\ & \approx 2.234848984 \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 2 primes p\frak{p} of bad reduction.

p\mathfrak{p} N(p)N(\mathfrak{p}) Tamagawa number Kodaira symbol Reduction type Root number ordp(N\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}) ordp(Dmin\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}) ordp(den(j))\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))
(a+2)(-a+2) 22 44 I12I_{12}^{*} Additive 1-1 44 2020 88
(3)(3) 99 11 I1I_{1} Non-split multiplicative 11 11 11 11

Galois Representations

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

prime Image of Galois Representation
22 2B

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree dd for d=d= 2, 4 and 8.
Its isogeny class 144.4-d consists of curves linked by isogenies of degrees dividing 8.

Base change

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

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