# Properties

 Label 438993.b1 Conductor $438993$ Discriminant $-22721838687$ j-invariant $$-\frac{32312399988051}{1154389}$$ CM no Rank $0$ Torsion structure trivial

# Related objects

Show commands: Magma / Oscar / PariGP / SageMath

## Simplified equation

 $$y^2+xy=x^3-x^2-17916x+927539$$ y^2+xy=x^3-x^2-17916x+927539 (homogenize, simplify) $$y^2z+xyz=x^3-x^2z-17916xz^2+927539z^3$$ y^2z+xyz=x^3-x^2z-17916xz^2+927539z^3 (dehomogenize, simplify) $$y^2=x^3-286659x+59075838$$ y^2=x^3-286659x+59075838 (homogenize, minimize)

comment: Define the curve

sage: E = EllipticCurve([1, -1, 0, -17916, 927539])

gp: E = ellinit([1, -1, 0, -17916, 927539])

magma: E := EllipticCurve([1, -1, 0, -17916, 927539]);

oscar: E = EllipticCurve([1, -1, 0, -17916, 927539])

sage: E.short_weierstrass_model()

magma: WeierstrassModel(E);

oscar: short_weierstrass_model(E)

## Mordell-Weil group structure

trivial

magma: MordellWeilGroup(E);

## Integral points

None

comment: Integral points

sage: E.integral_points()

magma: IntegralPoints(E);

## Invariants

 Conductor: $$438993$$ = $3^{3} \cdot 71 \cdot 229$ comment: Conductor  sage: E.conductor().factor()  gp: ellglobalred(E)[1]  magma: Conductor(E);  oscar: conductor(E) Discriminant: $-22721838687$ = $-1 \cdot 3^{9} \cdot 71^{2} \cdot 229$ comment: Discriminant  sage: E.discriminant().factor()  gp: E.disc  magma: Discriminant(E);  oscar: discriminant(E) j-invariant: $$-\frac{32312399988051}{1154389}$$ = $-1 \cdot 3^{6} \cdot 71^{-2} \cdot 229^{-1} \cdot 3539^{3}$ comment: j-invariant  sage: E.j_invariant().factor()  gp: E.j  magma: jInvariant(E);  oscar: j_invariant(E) Endomorphism ring: $\Z$ Geometric endomorphism ring: $$\Z$$ (no potential complex multiplication) sage: E.has_cm()  magma: HasComplexMultiplication(E); Sato-Tate group: $\mathrm{SU}(2)$ Faltings height: $1.0763050663592262169684540045\dots$ gp: ellheight(E)  magma: FaltingsHeight(E);  oscar: faltings_height(E) Stable Faltings height: $0.25234584985814394842202007681\dots$ magma: StableFaltingsHeight(E);  oscar: stable_faltings_height(E) $abc$ quality: $0.8285597031592442\dots$ Szpiro ratio: $3.155271797495679\dots$

## BSD invariants

 Analytic rank: $0$ sage: E.analytic_rank()  gp: ellanalyticrank(E)  magma: AnalyticRank(E); Regulator: $1$ comment: Regulator  sage: E.regulator()  G = E.gen \\ if available matdet(ellheightmatrix(E,G))  magma: Regulator(E); Real period: $1.1261754739056918198834766409\dots$ 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: $6$  = $3\cdot2\cdot1$ 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: $1$ comment: Torsion order  sage: E.torsion_order()  gp: elltors(E)[1]  magma: Order(TorsionSubgroup(E));  oscar: prod(torsion_structure(E)[1]) Analytic order of Ш: $1$ ( exact) comment: Order of Sha  sage: E.sha().an_numerical()  magma: MordellWeilShaInformation(E); Special value: $L(E,1)$ ≈ $6.7570528434341509193008598452$ 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);

## BSD formula

$\displaystyle 6.757052843 \approx L(E,1) = \frac{\# Ш(E/\Q)\cdot \Omega_E \cdot \mathrm{Reg}(E/\Q) \cdot \prod_p c_p}{\#E(\Q)_{\rm tor}^2} \approx \frac{1 \cdot 1.126175 \cdot 1.000000 \cdot 6}{1^2} \approx 6.757052843$

# 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 analyiic 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 438993.2.a.b

$$q + q^{2} - q^{4} + 2 q^{5} + 2 q^{7} - 3 q^{8} + 2 q^{10} + 6 q^{11} - 2 q^{13} + 2 q^{14} - q^{16} + 4 q^{17} + 7 q^{19} + O(q^{20})$$

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);

Modular degree: 931104
comment: Modular degree

sage: E.modular_degree()

gp: ellmoddegree(E)

magma: ModularDegree(E);

$\Gamma_0(N)$-optimal: yes
Manin constant: 1
comment: Manin constant

magma: ManinConstant(E);

## Local data

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

prime Tamagawa number Kodaira symbol Reduction type Root number ord($N$) ord($\Delta$) ord$(j)_{-}$
$3$ $3$ $IV^{*}$ Additive -1 3 9 0
$71$ $2$ $I_{2}$ Split multiplicative -1 1 2 2
$229$ $1$ $I_{1}$ Split multiplicative -1 1 1 1

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 $\ell$.

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 = [[1373, 2, 1372, 3], [235, 2, 235, 3], [1, 0, 2, 1], [1, 2, 0, 1], [917, 2, 917, 3], [1, 1, 1373, 0]]

GL(2,Integers(1374)).subgroup(gens)

Gens := [[1373, 2, 1372, 3], [235, 2, 235, 3], [1, 0, 2, 1], [1, 2, 0, 1], [917, 2, 917, 3], [1, 1, 1373, 0]];

sub<GL(2,Integers(1374))|Gens>;

The image $H:=\rho_E(\Gal(\overline{\Q}/\Q))$ of the adelic Galois representation has level $$1374 = 2 \cdot 3 \cdot 229$$, index $2$, genus $0$, and generators

$\left(\begin{array}{rr} 1373 & 2 \\ 1372 & 3 \end{array}\right),\left(\begin{array}{rr} 235 & 2 \\ 235 & 3 \end{array}\right),\left(\begin{array}{rr} 1 & 0 \\ 2 & 1 \end{array}\right),\left(\begin{array}{rr} 1 & 2 \\ 0 & 1 \end{array}\right),\left(\begin{array}{rr} 917 & 2 \\ 917 & 3 \end{array}\right),\left(\begin{array}{rr} 1 & 1 \\ 1373 & 0 \end{array}\right)$.

Input positive integer $m$ to see the generators of the reduction of $H$ to $\mathrm{GL}_2(\Z/m\Z)$:

The torsion field $K:=\Q(E[1374])$ is a degree-$394271608320$ Galois extension of $\Q$ with $\Gal(K/\Q)$ isomorphic to the projection of $H$ to $\GL_2(\Z/1374\Z)$.

## Isogenies

gp: ellisomat(E)

This curve has no rational isogenies. Its isogeny class 438993.b consists of this curve only.

## Twists

The minimal quadratic twist of this elliptic curve is 438993.a1, its twist by $-3$.

## Iwasawa invariants

No Iwasawa invariant data is available for this curve.

## $p$-adic regulators

All $p$-adic regulators are identically $1$ since the rank is $0$.