sage:from sage.modular.dirichlet import DirichletCharacter
H = DirichletGroup(2888, base_ring=CyclotomicField(2))
chi = DirichletCharacter(H, H._module([1, 1, 0]))
N = Newforms(chi, 1, names="a")
magma://Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
chi := DirichletCharacter("2888.723");
S:= CuspForms(chi, 1);
N := Newforms(S);
sage:f.q_expansion() # note that sage often uses an isomorphic number field
gp:mfcoefs(f, 20)
Coefficients of the q-expansion are expressed in terms of a basis 1,β1,β2 for the coefficient ring described below.
We also show the integral q-expansion of the trace form.