# Properties

 Label 3.3.49.1-71.2-a1 Base field $$\Q(\zeta_{7})^+$$ Conductor $$(-3a^2+4a+5)$$ Conductor norm $$71$$ CM no Base change no Q-curve no Torsion order $$2$$ Rank $$0$$

# Related objects

Show commands for: Magma / Pari/GP / SageMath

## Base field$$\Q(\zeta_{7})^+$$

Generator $$a$$, with minimal polynomial $$x^{3} - x^{2} - 2 x + 1$$; class number $$1$$.

sage: R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([1, -2, -1, 1]))

gp: K = nfinit(Pol(Vecrev([1, -2, -1, 1])));

magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![1, -2, -1, 1]);

## Weierstrass equation

$${y}^2+{x}{y}+\left(a^{2}+a-2\right){y}={x}^{3}+\left(-a^{2}+a+1\right){x}^{2}+\left(410a^{2}-221a-960\right){x}+5309a^{2}-2926a-12013$$
sage: E = EllipticCurve([K([1,0,0]),K([1,1,-1]),K([-2,1,1]),K([-960,-221,410]),K([-12013,-2926,5309])])

gp: E = ellinit([Pol(Vecrev([1,0,0])),Pol(Vecrev([1,1,-1])),Pol(Vecrev([-2,1,1])),Pol(Vecrev([-960,-221,410])),Pol(Vecrev([-12013,-2926,5309]))], K);

magma: E := EllipticCurve([K![1,0,0],K![1,1,-1],K![-2,1,1],K![-960,-221,410],K![-12013,-2926,5309]]);

This is a global minimal model.

sage: E.is_global_minimal_model()

## Invariants

 Conductor: $$(-3a^2+4a+5)$$ = $$(-3a^2+4a+5)$$ sage: E.conductor()  gp: ellglobalred(E)[1]  magma: Conductor(E); Conductor norm: $$71$$ = $$71$$ sage: E.conductor().norm()  gp: idealnorm(ellglobalred(E)[1])  magma: Norm(Conductor(E)); Discriminant: $$(1345154a^2-1063665a-1453060)$$ = $$(-3a^2+4a+5)^{10}$$ sage: E.discriminant()  gp: E.disc  magma: Discriminant(E); Discriminant norm: $$-3255243551009881201$$ = $$71^{10}$$ sage: E.discriminant().norm()  gp: norm(E.disc)  magma: Norm(Discriminant(E)); j-invariant: $$-\frac{1936929577866441496465968}{3255243551009881201} a^{2} + \frac{1128735985778740212430417}{3255243551009881201} a + \frac{4305562573648739958450652}{3255243551009881201}$$ sage: E.j_invariant()  gp: E.j  magma: jInvariant(E); Endomorphism ring: $$\Z$$ Geometric endomorphism ring: $$\Z$$ (no potential complex multiplication) sage: E.has_cm(), E.cm_discriminant()  magma: HasComplexMultiplication(E); Sato-Tate group: $\mathrm{SU}(2)$

## Mordell-Weil group

 Rank: $$0$$ Torsion structure: $$\Z/2\Z$$ sage: T = E.torsion_subgroup(); T.invariants()  gp: T = elltors(E); T[2]  magma: T,piT := TorsionSubgroup(E); Invariants(T); Torsion generator: $\left(11 a^{2} - 7 a - \frac{69}{4} : -6 a^{2} + 3 a + \frac{77}{8} : 1\right)$ sage: T.gens()  gp: T[3]  magma: [piT(P) : P in Generators(T)];

## BSD invariants

 Analytic rank: $$0$$ sage: E.rank()  magma: Rank(E); Mordell-Weil rank: $$0$$ Regulator: $$1$$ Period: $$1.64480363885333$$ Tamagawa product: $$10$$ Torsion order: $$2$$ Leading coefficient: $$0.587429871019048$$ Analytic order of Ш: $$1$$ (rounded)

## Local data at primes of bad reduction

sage: E.local_data()

magma: LocalInformation(E);

prime Norm Tamagawa number Kodaira symbol Reduction type Root number ord($$\mathfrak{N}$$) ord($$\mathfrak{D}$$) ord$$(j)_{-}$$
$$(-3a^2+4a+5)$$ $$71$$ $$10$$ $$I_{10}$$ Split multiplicative $$-1$$ $$1$$ $$10$$ $$10$$

## 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
$$5$$ 5B.1.2

## Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree $$d$$ for $$d=$$ 2, 5 and 10.
Its isogeny class 71.2-a consists of curves linked by isogenies of degrees dividing 10.

## Base change

This curve is not the base change of an elliptic curve defined over $$\Q$$. It is not a $$\Q$$-curve.