# SageMath code for working with modular form 3600.2.x.e # Compute space of new eigenforms: from sage.modular.dirichlet import DirichletCharacter H = DirichletGroup(3600, base_ring=CyclotomicField(4)) chi = DirichletCharacter(H, H._module([2, 0, 0, 3])) N = Newforms(chi, 2, names="a") # select newform: traces = [4,0,0,0,0,0,0,0,0,0,0,0,-4,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,-20,0,0,0,-8,0,0,0,0,0,0,0,0,0,0,0,-28,0,0,0,0,0,0,0,24,0, 0,0,0,0,0,0,0,0,0,0,28,0,0,0,24,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 28,0,0,0,40] f = next(g for g in N if [g.coefficient(i+1).trace() for i in range(101)] == traces) # q-expansion: f.q_expansion() # note that sage often uses an isomorphic number field