By Doron Zeilberger
Written: April 25, 2004.
This is the transcript of my talk given, on June 30, 2003, at Dave Robbins's 60th Birthday Conference, wonderfully organized by Lynne Butler and Clara Chan. Sadly Dave Robbins died about two months later. This article is intended for a Special Issue of Adv. Appl. Math. in memory of Dave Robbins, guest-edited by Dave Bressoud and Bill Doran.
IMPORTANT: This article is accompanied by two short Maple progrmams.