Re: Regard hecke operators in half integer weight setting

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Sat, Sep 14, 2024 at 02:13:01PM +0000, LNU, Swati wrote:
> Hello,
> I am trying to code the Fourier expansion of f | T_{p^2} for a half integer
> weight modular form but I am getting incorrect type in gtos error.
> Here is my code:
> 
> S(f, p, k) = {f = truncate(f); sum(n = 1, poldegree(f), (polcoeff(f, (n * p^2))) + (kronecker(-4, n)^(k - (1/2)) * kronecker(12 * n,p) * p^(k - (3/2)) * polcoeff(f, n)) + (sumdiv(n, p, p^((2 * k)- 2) * polcoeff(f, n/p^2))) * q^n) + O(q^(poldegree(f) + 1));}

Please copy-paste the command that triggers the error, thanks.

Cheers,
Bill.