Just a question/remark : a DeBruijn sequence is just a Hamiltonian cycle in the Rauzy graph of the full language right ? (remark that for the DeBruijn graph the problem of finding Hamiltonian path is equivalent to the one of looking for Euler cycles at the next level!). It could be nice to have pointers from the DeBruijn graph...
> > Ok. So the set of all factors of a word is a factorial language. The > converse does not hold, right? Out of curiosity, is there a > characterization of those factorial languages that come from a word? > When I say maximal element, it is for the relation "contains x as factor". * if the word is finite : there is a maximal element which is the word itself. * if the word is infinite : you adapt the preceding definition at all finite steps : for all n there exists a word w in L such that w contains all words of length n of L. In other words, each finite subset admit a maximal element in L. > > Now, would it make sense to have a Languages category? With > FactorialLanguages as subcategory? What kind of operations would those > provide on parents (the languages), elements (their words), and morphisms? > It could be useful to have the category framework because for a word morphism the image of the language of w is not the the language of the image... Cheers, Vincent -- You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-de...@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
