magma://Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
chi := DirichletCharacter("528.175");
S:= CuspForms(chi, 6);
N := Newforms(S);
sage:from sage.modular.dirichlet import DirichletCharacter
H = DirichletGroup(528, base_ring=CyclotomicField(2))
chi = DirichletCharacter(H, H._module([1, 0, 0, 1]))
N = Newforms(chi, 6, names="a")
This newform subspace can be constructed as the kernel of the linear operator
\( T_{5}^{10} - 22 T_{5}^{9} - 16066 T_{5}^{8} + 342128 T_{5}^{7} + 84406964 T_{5}^{6} + \cdots + 11\!\cdots\!28 \)
acting on \(S_{6}^{\mathrm{new}}(528, [\chi])\).