Zeilberger has made contributions to combinatorics,
hypergeometric identities, and
q-series. He gave the first proof of the
alternating sign matrix conjecture, noteworthy not only for its mathematical content, but also for the fact that Zeilberger recruited nearly a hundred volunteer checkers to "pre-referee" the paper. In 2011, together with
Manuel Kauers and
Christoph Koutschan, Zeilberger proved the
q-TSPP conjecture, which was independently stated in 1983 by
George Andrews and
David P. Robbins. Zeilberger is an
ultrafinitist. He is also known for crediting his computer "Shalosh B. Ekhad" as a co-author ("Shalosh" and "Ekhad" mean "Three" and "One" in
Hebrew respectively, referring to his first computer, an
AT&T 3B1), and for his provocative opinions published on his "Dr. Z's Opinions" page. ==Awards and honors==