nanshe/nanshe/additional_generators.py: Allow `n` to be `0` in both cases.
nanshe/nanshe/additional_generators.py: Allow `n` to be `0` in both cases.

DudLab/nanshe,nanshe-org/nanshe,nanshe-org/nanshe,DudLab/nanshe,jakirkham/nanshe,jakirkham/nanshe