Properties

Base field 5.5.36497.1
Label 5.5.36497.1-25.1-a1
Conductor \((5,-a^{2} + 2 a + 2)\)
Conductor norm \( 25 \)
CM no
base-change no
Q-curve not determined
Torsion order \( 4 \)
Rank not available

Related objects

Downloads

Learn more about

Show commands for: Magma / SageMath / Pari/GP

Base field 5.5.36497.1

Generator \(a\), with minimal polynomial \( x^{5} - 2 x^{4} - 3 x^{3} + 5 x^{2} + x - 1 \); class number \(1\).

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-1, 1, 5, -3, -2, 1]);
sage: x = polygen(QQ); K.<a> = NumberField(x^5 - 2*x^4 - 3*x^3 + 5*x^2 + x - 1)
gp (2.8): K = nfinit(a^5 - 2*a^4 - 3*a^3 + 5*a^2 + a - 1);

Weierstrass equation

\( y^2 + \left(2 a^{4} - 3 a^{3} - 6 a^{2} + 7 a + 1\right) x y + \left(a^{4} - 2 a^{3} - 2 a^{2} + 4 a - 1\right) y = x^{3} + \left(-2 a^{4} + 3 a^{3} + 8 a^{2} - 7 a - 5\right) x^{2} + \left(2 a^{4} - 2 a^{3} - 4 a^{2} + 4 a\right) x + 2 a^{4} - a^{3} - 5 a^{2} + 2 a \)
magma: E := ChangeRing(EllipticCurve([2*a^4 - 3*a^3 - 6*a^2 + 7*a + 1, -2*a^4 + 3*a^3 + 8*a^2 - 7*a - 5, a^4 - 2*a^3 - 2*a^2 + 4*a - 1, 2*a^4 - 2*a^3 - 4*a^2 + 4*a, 2*a^4 - a^3 - 5*a^2 + 2*a]),K);
sage: E = EllipticCurve(K, [2*a^4 - 3*a^3 - 6*a^2 + 7*a + 1, -2*a^4 + 3*a^3 + 8*a^2 - 7*a - 5, a^4 - 2*a^3 - 2*a^2 + 4*a - 1, 2*a^4 - 2*a^3 - 4*a^2 + 4*a, 2*a^4 - a^3 - 5*a^2 + 2*a])
gp (2.8): E = ellinit([2*a^4 - 3*a^3 - 6*a^2 + 7*a + 1, -2*a^4 + 3*a^3 + 8*a^2 - 7*a - 5, a^4 - 2*a^3 - 2*a^2 + 4*a - 1, 2*a^4 - 2*a^3 - 4*a^2 + 4*a, 2*a^4 - a^3 - 5*a^2 + 2*a],K)

This is a global minimal model.

sage: E.is_global_minimal_model()

Invariants

\(\mathfrak{N} \) = \((5,-a^{2} + 2 a + 2)\) = \( \left(a^{4} - 2 a^{3} - 2 a^{2} + 5 a\right) \)
magma: Conductor(E);
sage: E.conductor()
\(N(\mathfrak{N}) \) = \( 25 \) = \( 25 \)
magma: Norm(Conductor(E));
sage: E.conductor().norm()
\(\mathfrak{D}\) = \((25,25 a,a^{4} - 2 a^{3} - 3 a^{2} + 7 a + 2,a^{4} - a^{3} - 4 a^{2} + 13 a + 20,a^{2} + 13 a + 13)\) = \( \left(a^{4} - 2 a^{3} - 2 a^{2} + 5 a\right)^{2} \)
magma: Discriminant(E);
sage: E.discriminant()
gp (2.8): E.disc
\(N(\mathfrak{D})\) = \( 625 \) = \( 25^{2} \)
magma: Norm(Discriminant(E));
sage: E.discriminant().norm()
gp (2.8): norm(E.disc)
\(j\) = \( \frac{708112}{25} a^{4} - \frac{1125079}{25} a^{3} - \frac{2581192}{25} a^{2} + \frac{496376}{5} a + \frac{1711623}{25} \)
magma: jInvariant(E);
sage: E.j_invariant()
gp (2.8): E.j
\( \text{End} (E) \) = \(\Z\)   (no Complex Multiplication )
magma: HasComplexMultiplication(E);
sage: E.has_cm(), E.cm_discriminant()
\( \text{ST} (E) \) = $\mathrm{SU}(2)$

Mordell-Weil rank and generators

Rank not available.
magma: Rank(E);
sage: E.rank()
magma: Generators(E); // includes torsion
sage: E.gens()

Regulator: not available

magma: Regulator(Generators(E));
sage: E.regulator_of_points(E.gens())

Torsion subgroup

Structure: \(\Z/4\Z\)
magma: TorsionSubgroup(E);
sage: E.torsion_subgroup().gens()
gp (2.8): elltors(E)[2]
magma: Order(TorsionSubgroup(E));
sage: E.torsion_order()
gp (2.8): elltors(E)[1]
Generator: $\left(-a^{4} + a^{3} + 3 a^{2} - a : a^{4} - 4 a^{2} - a + 1 : 1\right)$
magma: [f(P): P in Generators(T)] where T,f:=TorsionSubgroup(E);
sage: E.torsion_subgroup().gens()
gp (2.8): elltors(E)[3]

Local data at primes of bad reduction

magma: LocalInformation(E);
sage: E.local_data()
prime Norm Tamagawa number Kodaira symbol Reduction type ord(\(\mathfrak{N}\)) ord(\(\mathfrak{D}\)) ord\((j)_{-}\)
\( \left(a^{4} - 2 a^{3} - 2 a^{2} + 5 a\right) \) 25 \(2\) \( I_{2} \) Split multiplicative 1 2 2

Galois Representations

The mod \( p \) Galois Representation has maximal image for all primes \( p \) except those listed.

prime Image of Galois Representation
\(2\) 2B

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2 and 4.
Its isogeny class 25.1-a consists of curves linked by isogenies of degrees dividing 4.

Base change

This curve is not the base-change of an elliptic curve defined over \(\Q\). It has not yet been determined whether or not it is a \(\Q\)-curve.