Circular words and applications
  We define the notion of circular words, then consider on such words a constraint derived from the Fibonacci condition. We give several results on the structure of these circular words, then mention possible applications to various situations: periodic expansion of numbers in numeration systems, "gcd-property" of integer sequences, partition of the prefix of the fixed point of the Fibonacci substitution, spanning trees of a wheel. Eventually, we mention some open questions. 
Beno\^it Rittaud (Laboratoire Analyse, G\'eom\'etrie et Applications,   Institut Galil\'ee, Universit\'e Paris-13), Laurent ...
cs.FL math.CO