The LSV seminar takes place on Tuesday at 11:00 AM. The usual location is the conference room at Pavillon des Jardins (venue). If you wish to be informed by e-mail about upcoming seminars, please contact Stéphane Le Roux and Matthias Fuegger.
The seminar is open to public and does not require any form of registration.
We investigate the infinite-words which are frontiers of solutions of recursive schemes, i.e. leaves by lexicographic order of infinite trees. For order-1 schemes, they are exactly the morphic words, i.e. images of fixpoints of morphisms of words. We extend this result to solutions of order-2 schemes, and introduce 2-morphic words. Safety is not a restriction when considering a specific tree shape, so these words are exactly the words of the corresponding level in the pushdown hierarchy and enjoy the associated properties.