torsion 15

K.<a> = NumberField(x^2 - x -1) E10a = EllipticCurve([a,a-1,a+1,-a,-a]) E10b = EllipticCurve(K,[1,0,1,-1,-2]) E10x = EllipticCurve([(281880*(2*a-1) - 630315), 328392630 - 146861640*(2*a-1)]) print E10a.conductor() print E10b.conductor() print E10x.conductor() 

Fractional ideal (10)
Fractional ideal (10)
Fractional ideal (10)

Fractional ideal (10)
Fractional ideal (10)
Fractional ideal (10)

T = E10x.torsion_subgroup() t = T.gens()[0] t3 = 3*t t5 = 5*t 

i = E10x.isogenies_prime_degree() E10x1 = i[0].codomain() E10x2 = i[1].codomain()