%0 Journal Article %T A formula for the number of tilings of an octagon by rhombi %A N. Destainville %A R. Mosseri %A F. Bailly %J Mathematics %D 2003 %I arXiv %X We propose the first algebraic determinantal formula to enumerate tilings of a centro-symmetric octagon of any size by rhombi. This result uses the Gessel-Viennot technique and generalizes to any octagon a formula given by Elnitsky in a special case. %U http://arxiv.org/abs/math/0302105v2