a1 Université de Rouen, LIFAR, 75821 Mont Saint Aignan Cedex, France; jean.francis.michon@univ-rouen.fr; pierre.valarcher@univ-rouen.fr
a2 Université Paris 7, LIAFA, 175 rue du Chevaleret, 75013 Paris, France; Jean-Baptiste.Yunes@liafa.jussieu.fr
Abstract
We investigate the structure of “worst-case” quasi reduced ordered decision diagrams and Boolean functions whose truth tables are associated to: we suggest different ways to count and enumerate them. We, then, introduce a notion of complexity which leads to the concept of “hard” Boolean functions as functions whose QROBDD are “worst-case” ones. So we exhibit the relation between hard functions and the Storage Access function (also known as Multiplexer).
(Received March 2003)
(Accepted December 2004)
(Online publication October 15 2005)
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