Properties

Label 5415k1
Conductor 54155415
Discriminant 705688215-705688215
j-invariant 115 -\frac{1}{15}
CM no
Rank 00
Torsion structure Z/2Z\Z/{2}\Z

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Show commands: Magma / Oscar / PariGP / SageMath

Minimal Weierstrass equation

Minimal Weierstrass equation

Simplified equation

y2+xy+y=x38x1279y^2+xy+y=x^3-8x-1279 Copy content Toggle raw display (homogenize, simplify)
y2z+xyz+yz2=x38xz21279z3y^2z+xyz+yz^2=x^3-8xz^2-1279z^3 Copy content Toggle raw display (dehomogenize, simplify)
y2=x39747x59632146y^2=x^3-9747x-59632146 Copy content Toggle raw display (homogenize, minimize)

comment: Define the curve
 
sage: E = EllipticCurve([1, 0, 1, -8, -1279])
 
gp: E = ellinit([1, 0, 1, -8, -1279])
 
magma: E := EllipticCurve([1, 0, 1, -8, -1279]);
 
oscar: E = elliptic_curve([1, 0, 1, -8, -1279])
 
sage: E.short_weierstrass_model()
 
magma: WeierstrassModel(E);
 
oscar: short_weierstrass_model(E)
 

Mordell-Weil group structure

Z/2Z\Z/{2}\Z

magma: MordellWeilGroup(E);
 

Mordell-Weil generators

PPh^(P)\hat{h}(P)Order
(11,6)(11, -6)0022

Integral points

(11,6) \left(11, -6\right) Copy content Toggle raw display

comment: Integral points
 
sage: E.integral_points()
 
magma: IntegralPoints(E);
 

Invariants

Conductor: NN  =  5415 5415  = 351923 \cdot 5 \cdot 19^{2}
comment: Conductor
 
sage: E.conductor().factor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
oscar: conductor(E)
 
Discriminant: Δ\Delta  =  705688215-705688215 = 135196-1 \cdot 3 \cdot 5 \cdot 19^{6}
comment: Discriminant
 
sage: E.discriminant().factor()
 
gp: E.disc
 
magma: Discriminant(E);
 
oscar: discriminant(E)
 
j-invariant: jj  =  115 -\frac{1}{15}  = 13151-1 \cdot 3^{-1} \cdot 5^{-1}
comment: j-invariant
 
sage: E.j_invariant().factor()
 
gp: E.j
 
magma: jInvariant(E);
 
oscar: j_invariant(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)
sage: E.has_cm()
 
magma: HasComplexMultiplication(E);
 
Sato-Tate group: ST(E)\mathrm{ST}(E) = SU(2)\mathrm{SU}(2)
Faltings height: hFaltingsh_{\mathrm{Faltings}} ≈ 0.376794736940431133143685097320.37679473694043113314368509732
gp: ellheight(E)
 
magma: FaltingsHeight(E);
 
oscar: faltings_height(E)
 
Stable Faltings height: hstableh_{\mathrm{stable}} ≈ 1.0954247526427890968608286186-1.0954247526427890968608286186
magma: StableFaltingsHeight(E);
 
oscar: stable_faltings_height(E)
 
abcabc quality: QQ ≈ 1.19807684405159481.1980768440515948
Szpiro ratio: σm\sigma_{m} ≈ 3.23713797403609553.2371379740360955

BSD invariants

Analytic rank: ranr_{\mathrm{an}} = 0 0
sage: E.analytic_rank()
 
gp: ellanalyticrank(E)
 
magma: AnalyticRank(E);
 
Mordell-Weil rank: rr = 0 0
comment: Rank
 
sage: E.rank()
 
gp: [lower,upper] = ellrank(E)
 
magma: Rank(E);
 
Regulator: Reg(E/Q)\mathrm{Reg}(E/\Q) = 11
comment: Regulator
 
sage: E.regulator()
 
G = E.gen \\ if available
 
matdet(ellheightmatrix(E,G))
 
magma: Regulator(E);
 
Real period: Ω\Omega ≈ 0.732406161651078768585664853610.73240616165107876858566485361
comment: Real Period
 
sage: E.period_lattice().omega()
 
gp: if(E.disc>0,2,1)*E.omega[1]
 
magma: (Discriminant(E) gt 0 select 2 else 1) * RealPeriod(E);
 
Tamagawa product: pcp\prod_{p}c_p = 4 4  = 1122 1\cdot1\cdot2^{2}
comment: Tamagawa numbers
 
sage: E.tamagawa_numbers()
 
gp: gr=ellglobalred(E); [[gr[4][i,1],gr[5][i][4]] | i<-[1..#gr[4][,1]]]
 
magma: TamagawaNumbers(E);
 
oscar: tamagawa_numbers(E)
 
Torsion order: #E(Q)tor\#E(\Q)_{\mathrm{tor}} = 22
comment: Torsion order
 
sage: E.torsion_order()
 
gp: elltors(E)[1]
 
magma: Order(TorsionSubgroup(E));
 
oscar: prod(torsion_structure(E)[1])
 
Special value: L(E,1) L(E,1) ≈ 2.92962464660431507434265941452.9296246466043150743426594145
comment: Special L-value
 
r = E.rank();
 
E.lseries().dokchitser().derivative(1,r)/r.factorial()
 
gp: [r,L1r] = ellanalyticrank(E); L1r/r!
 
magma: Lr1 where r,Lr1 := AnalyticRank(E: Precision:=12);
 
Analytic order of Ш: Шan{}_{\mathrm{an}}  =  44 = 222^2    (exact)
comment: Order of Sha
 
sage: E.sha().an_numerical()
 
magma: MordellWeilShaInformation(E);
 

BSD formula

2.929624647L(E,1)=#Ш(E/Q)ΩEReg(E/Q)pcp#E(Q)tor240.7324061.0000004222.929624647\displaystyle 2.929624647 \approx L(E,1) = \frac{\# Ш(E/\Q)\cdot \Omega_E \cdot \mathrm{Reg}(E/\Q) \cdot \prod_p c_p}{\#E(\Q)_{\rm tor}^2} \approx \frac{4 \cdot 0.732406 \cdot 1.000000 \cdot 4}{2^2} \approx 2.929624647

# self-contained SageMath code snippet for the BSD formula (checks rank, computes analytic sha)
 
E = EllipticCurve(%s); r = E.rank(); ar = E.analytic_rank(); assert r == ar;
 
Lr1 = E.lseries().dokchitser().derivative(1,r)/r.factorial(); sha = E.sha().an_numerical();
 
omega = E.period_lattice().omega(); reg = E.regulator(); tam = E.tamagawa_product(); tor = E.torsion_order();
 
assert r == ar; print("analytic sha: " + str(RR(Lr1) * tor^2 / (omega * reg * tam)))
 
/* self-contained Magma code snippet for the BSD formula (checks rank, computes analytic sha) */
 
E := EllipticCurve(%s); r := Rank(E); ar,Lr1 := AnalyticRank(E: Precision := 12); assert r eq ar;
 
sha := MordellWeilShaInformation(E); omega := RealPeriod(E) * (Discriminant(E) gt 0 select 2 else 1);
 
reg := Regulator(E); tam := &*TamagawaNumbers(E); tor := #TorsionSubgroup(E);
 
assert r eq ar; print "analytic sha:", Lr1 * tor^2 / (omega * reg * tam);
 

Modular invariants

Modular form   5415.2.a.j

q+q2+q3q4+q5+q63q8+q9+q104q11q12+2q13+q15q16+2q17+q18+O(q20) q + q^{2} + q^{3} - q^{4} + q^{5} + q^{6} - 3 q^{8} + q^{9} + q^{10} - 4 q^{11} - q^{12} + 2 q^{13} + q^{15} - q^{16} + 2 q^{17} + q^{18} + O(q^{20}) Copy content Toggle raw display

comment: q-expansion of modular form
 
sage: E.q_eigenform(20)
 
\\ actual modular form, use for small N
 
[mf,F] = mffromell(E)
 
Ser(mfcoefs(mf,20),q)
 
\\ or just the series
 
Ser(ellan(E,20),q)*q
 
magma: ModularForm(E);
 

For more coefficients, see the Downloads section to the right.

Modular degree: 1728
comment: Modular degree
 
sage: E.modular_degree()
 
gp: ellmoddegree(E)
 
magma: ModularDegree(E);
 
Γ0(N) \Gamma_0(N) -optimal: yes
Manin constant: 1
comment: Manin constant
 
magma: ManinConstant(E);
 

Local data at primes of bad reduction

This elliptic curve is not semistable. There are 3 primes pp of bad reduction:

pp Tamagawa number Kodaira symbol Reduction type Root number ordp(N)\mathrm{ord}_p(N) ordp(Δ)\mathrm{ord}_p(\Delta) ordp(den(j))\mathrm{ord}_p(\mathrm{den}(j))
33 11 I1I_{1} split multiplicative -1 1 1 1
55 11 I1I_{1} split multiplicative -1 1 1 1
1919 44 I0I_0^{*} additive -1 2 6 0

comment: Local data
 
sage: E.local_data()
 
gp: ellglobalred(E)[5]
 
magma: [LocalInformation(E,p) : p in BadPrimes(E)];
 
oscar: [(p,tamagawa_number(E,p), kodaira_symbol(E,p), reduction_type(E,p)) for p in bad_primes(E)]
 

Galois representations

The \ell-adic Galois representation has maximal image for all primes \ell except those listed in the table below.

prime \ell mod-\ell image \ell-adic image
22 2B 32.48.0.1

comment: mod p Galois image
 
sage: rho = E.galois_representation(); [rho.image_type(p) for p in rho.non_surjective()]
 
magma: [GaloisRepresentation(E,p): p in PrimesUpTo(20)];
 

gens = [[23, 18, 6558, 7115], [1, 2432, 570, 6271], [1, 0, 32, 1], [6423, 5282, 5434, 7183], [1, 32, 0, 1], [5, 28, 68, 381], [7199, 0, 0, 9119], [1312, 8189, 4427, 1122], [9089, 32, 9088, 33], [1654, 3363, 1805, 7468]]
 
GL(2,Integers(9120)).subgroup(gens)
 
Gens := [[23, 18, 6558, 7115], [1, 2432, 570, 6271], [1, 0, 32, 1], [6423, 5282, 5434, 7183], [1, 32, 0, 1], [5, 28, 68, 381], [7199, 0, 0, 9119], [1312, 8189, 4427, 1122], [9089, 32, 9088, 33], [1654, 3363, 1805, 7468]];
 
sub<GL(2,Integers(9120))|Gens>;
 

The image H:=ρE(Gal(Q/Q))H:=\rho_E(\Gal(\overline{\Q}/\Q)) of the adelic Galois representation has level 9120=253519 9120 = 2^{5} \cdot 3 \cdot 5 \cdot 19 , index 768768, genus 1313, and generators

(231865587115),(124325706271),(10321),(6423528254347183),(13201),(52868381),(7199009119),(1312818944271122),(908932908833),(1654336318057468)\left(\begin{array}{rr} 23 & 18 \\ 6558 & 7115 \end{array}\right),\left(\begin{array}{rr} 1 & 2432 \\ 570 & 6271 \end{array}\right),\left(\begin{array}{rr} 1 & 0 \\ 32 & 1 \end{array}\right),\left(\begin{array}{rr} 6423 & 5282 \\ 5434 & 7183 \end{array}\right),\left(\begin{array}{rr} 1 & 32 \\ 0 & 1 \end{array}\right),\left(\begin{array}{rr} 5 & 28 \\ 68 & 381 \end{array}\right),\left(\begin{array}{rr} 7199 & 0 \\ 0 & 9119 \end{array}\right),\left(\begin{array}{rr} 1312 & 8189 \\ 4427 & 1122 \end{array}\right),\left(\begin{array}{rr} 9089 & 32 \\ 9088 & 33 \end{array}\right),\left(\begin{array}{rr} 1654 & 3363 \\ 1805 & 7468 \end{array}\right).

Input positive integer mm to see the generators of the reduction of HH to GL2(Z/mZ)\mathrm{GL}_2(\Z/m\Z):

The torsion field K:=Q(E[9120])K:=\Q(E[9120]) is a degree-14523826176001452382617600 Galois extension of Q\Q with Gal(K/Q)\Gal(K/\Q) isomorphic to the projection of HH to GL2(Z/9120Z)\GL_2(\Z/9120\Z).

The table below list all primes \ell for which the Serre invariants associated to the mod-\ell Galois representation are exceptional.

\ell Reduction type Serre weight Serre conductor
33 split multiplicative 44 1805=5192 1805 = 5 \cdot 19^{2}
55 split multiplicative 66 1083=3192 1083 = 3 \cdot 19^{2}
1919 additive 182182 15=35 15 = 3 \cdot 5

Isogenies

gp: ellisomat(E)
 

This curve has non-trivial cyclic isogenies of degree dd for d=d= 2, 4, 8 and 16.
Its isogeny class 5415k consists of 8 curves linked by isogenies of degrees dividing 16.

Twists

The minimal quadratic twist of this elliptic curve is 15a8, its twist by 19-19.

Growth of torsion in number fields

The number fields KK of degree less than 24 such that E(K)torsE(K)_{\rm tors} is strictly larger than E(Q)torsE(\Q)_{\rm tors} Z/2Z\cong \Z/{2}\Z are as follows:

[K:Q][K:\Q] KK E(K)torsE(K)_{\rm tors} Base change curve
22 Q(15)\Q(\sqrt{-15}) Z/2ZZ/2Z\Z/2\Z \oplus \Z/2\Z not in database
22 Q(285)\Q(\sqrt{285}) Z/4Z\Z/4\Z not in database
22 Q(19)\Q(\sqrt{-19}) Z/4Z\Z/4\Z not in database
44 Q(15,19)\Q(\sqrt{-15}, \sqrt{-19}) Z/2ZZ/4Z\Z/2\Z \oplus \Z/4\Z not in database
44 Q(3,19)\Q(\sqrt{-3}, \sqrt{-19}) Z/8Z\Z/8\Z not in database
44 Q(5,19)\Q(\sqrt{5}, \sqrt{-19}) Z/8Z\Z/8\Z not in database
88 8.0.380016036000000.43 Z/2ZZ/4Z\Z/2\Z \oplus \Z/4\Z not in database
88 8.4.380016036000000.20 Z/8Z\Z/8\Z not in database
88 8.0.6597500625.1 Z/2ZZ/8Z\Z/2\Z \oplus \Z/8\Z not in database
88 8.0.2036265625.1 Z/16Z\Z/16\Z not in database
88 8.0.164937515625.1 Z/16Z\Z/16\Z not in database
88 8.2.14428733866875.2 Z/6Z\Z/6\Z not in database
1616 deg 16 Z/4ZZ/4Z\Z/4\Z \oplus \Z/4\Z not in database
1616 deg 16 Z/2ZZ/8Z\Z/2\Z \oplus \Z/8\Z not in database
1616 deg 16 Z/16Z\Z/16\Z not in database
1616 16.0.27204384060547119140625.1 Z/2ZZ/16Z\Z/2\Z \oplus \Z/16\Z not in database
1616 deg 16 Z/32Z\Z/32\Z not in database
1616 deg 16 Z/2ZZ/6Z\Z/2\Z \oplus \Z/6\Z not in database
1616 deg 16 Z/12Z\Z/12\Z not in database
1616 deg 16 Z/12Z\Z/12\Z not in database

We only show fields where the torsion growth is primitive. For fields not in the database, click on the degree shown to reveal the defining polynomial.

Iwasawa invariants

pp 2 3 5 19
Reduction type ord split split add
λ\lambda-invariant(s) 2 1 1 -
μ\mu-invariant(s) 0 0 0 -

All Iwasawa λ\lambda and μ\mu-invariants for primes p3p\ge 3 of good reduction are zero.

An entry - indicates that the invariants are not computed because the reduction is additive.

pp-adic regulators

All pp-adic regulators are identically 11 since the rank is 00.