-series

-series of

Thanks to wrapping work of Jennifer Balakrishnan of M.I.T., we can compute explicitly with the -series of the modular form . Like for elliptic curves, behind these scenes this uses Dokchitsers -functions calculation Pari program.

sage: L = delta_lseries(); L
L-series associated to the modular form Delta
sage: L(1)
0.0374412812685155

-series of a Cusp Form

In some cases we can also compute with -series attached to a cusp form.

sage: f = CuspForms(2,8).0
sage: L = f.cuspform_lseries()
sage: L(1)
0.0884317737041015
sage: L(0.5)
0.0296568512531983

-series of a General Newform is Not Implemented

Unfortunately, computing with the -series of a general newform is not yet implemented.

sage: S = CuspForms(23,2); S
Cuspidal subspace of dimension 2 of Modular Forms space of
dimension 3 for Congruence Subgroup Gamma0(23) of weight
2 over Rational Field
sage: f = S.newforms('a')[0]; f
q + a0*q^2 + (-2*a0 - 1)*q^3 + (-a0 - 1)*q^4 + 2*a0*q^5 + O(q^6)

Computing with totally not implemented yet, though should be easy via Dokchitser.