greenberg 11a -- rank over Q(zeta_5)

585 days ago by wstein

M = ModularSymbols(11,2) 
       
for eps in DirichletGroup(5): N = M.change_ring(eps.base_ring()) s = N.twisted_winding_element(0, eps) phi = N.cuspidal_submodule().rational_period_mapping() print phi(s) 
       
(-5, 0)
(5*zeta4, -2*zeta4)
(25, 0)
(-5*zeta4, 2*zeta4)
(-5, 0)
(5*zeta4, -2*zeta4)
(25, 0)
(-5*zeta4, 2*zeta4)
E = EllipticCurve('11a').change_ring(CyclotomicField(5)) 
       
E.torsion_order() 
       
25
25