On Fri, Jan 30, 2009 at 1:47 PM, Kim <khopk...@math.utexas.edu> wrote: > > Is there a way to compute coefficients of half-integral-weight modular > forms in Sage? > > Specifically I want the coefficients of the weight 5/2 form on Gamma_0 > (4*13) that is in Shimura-Kohnen correspondence with the weight 4 > newform (of degree 1) on Gamma_0(13). > > The first few coefficients of the weight 4 form are: q - 5*q^2 - 7*q^3 > + 17*q^4 - 7*q^5 +... > > (I can get the right coefficients up to sign using the Jacobi form of > weight 3 and index 13 but can't get the right signs of the > coefficients this way...)
There is a command in sage called half_integral_weight_modform_basis that you might find useful. Type sage: half_integral_weight_modform_basis? for examples and help. William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
