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  • @article{RISC3837,
    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}