I think this is a form of autogram: https://en.m.wikipedia.org/wiki/Autogram https://en.m.wikipedia.org/wiki/Autogram The article even provides a pair of mutua

I think this is a form of autogram: https://en.m.wikipedia.org/wiki/Autogram https://en.m.wikipedia.org/wiki/Autogram The article even provides a pair of mutually-describing sentences. Hofstadter has described these in at least one of his books, but I don't recall if he discussed how to generate them.