Elliptic enumeration of nonintersecting lattice paths

We enumerate lattice paths in the planar integer lattice consisting of positively directed unit vertical and horizontal steps with respect to a specific elliptic weight function. The elliptic generating function of paths from a given starting point to a given end point evaluates to an elliptic generalization of the binomial coefficient. Convolution gives an identity equivalent to Frenkel and Turaev's V-10(9) summation. This appears to be the first combinatoriall proof of the latter, and at the same time of some important degenerate cases including Jackson's 807 and Dougall's F-7(6) summation. By considering nonintersecting lattice paths we are led to a multivariate extension of the V-10(9) summation which turns out to be a special case of an identity originally conjectured by Warnaar, later proved by Rosengren. We conclude with discussing some future perspectives. (c) 2006 Elsevier Inc. All rights reserved.