1Function: mfbd
2Section: modular_forms
3C-Name: mfbd
4Prototype: GL
5Help: mfbd(F,d): F being a generalized modular form, return B(d)(F), where
6 B(d) is the expanding operator tau -> d tau.
7Doc: $F$ being a generalized modular form, return $B(d)(F)$, where $B(d)$ is
8 the expanding operator $\tau\mapsto d\tau$.
9 \bprog
10 ? D2=mfbd(mfDelta(),2); mfcoefs(D2, 6)
11 %1 = [0, 0, 1, 0, -24, 0, 252]
12 @eprog
13