Let Nn denote the quotient poset of the Boolean lattice, Bn, under the relation equivalence under rotation. Griggs, Killian, and Savage proved that Np is a symmetric chain order for prime p. In this paper, we settle the question of whether this poset is a symmetric chain order for all n by providing an algorithm that produces a symmetric chain decompostion (or SCD). We accomplish this by modify...

UIs as a long-term solution for non-visual access to GUIs Kris Van Hees, Jan Engelen Katholieke Universiteit Leuven Department of Electrical Engineering – ESAT – SCD – DocArch Kasteelpark Arenberg 10 B-3001 Heverlee-Leuven Belgium [email protected], [email protected]