# SageMath code for working with modular form 11025.2.a.bl # Compute space of new eigenforms: from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(11025, base_ring=CyclotomicField(2)) chi = DirichletCharacter(H, H._module([0, 0, 0])) N = Newforms(chi, 2, names="a") # select newform: traces = [1,1,0,-1,0,0,0,-3,0,0,2,0,6,0,0,-1,6,0,6,0,0,2,-4,0,0,6,0,0, -8,0,6,5,0,6,0,0,6,6,0,0,-6,0,0,-2,0,-4,0,0,0,0,0,-6,2,0,0,0,0,-8,-12, 0,0,6,0,7,0,0,-4,-6,0,0,14,0,-6,6,0,-6,0,0,8,0,0,-6,12,0,0,0,0,-6,6,0, 0,4,0,0,0,0,6,0,0,0] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(None)] == traces) # q-expansion: f.q_expansion() # note that sage often uses an isomorphic number field