author = {Manuel Kauers and Christoph Koutschan and Doron Zeilberger},
title = {{Proof of Ira Gessel's Lattice Path Conjecture}},
language = {english},
abstract = { We present a computer-aided, yet fully rigorous, proof of Ira Gessel's tantalizingly simply-stated conjecture that the number of ways of walking $2n$ steps in the region $x+y \geq 0, y \geq 0$ of the square-lattice with unit steps in the east, west, north, and south directions, that start and end at the origin, equals $16^n\frac{(5/6)_n(1/2)_n}{(5/3)_n(2)_n}$ .},
journal = {Proceedings of the National Academy of Sciences},
volume = {106},
number = {28},
pages = {11502--11505},
isbn_issn = {ISSN 0027-8424},
year = {2009},
month = {July},
refereed = {yes},
length = {4}