E.A.Tropp Dimensional interpolation and addition formulae for Jacobi polynomial and hypergeometric function (193K, ps) ABSTRACT. T. Koornwinder's addition formula for jacobi polinomials is in terms of partial differential equation with separable variables. The result provides a new proof of the addition formula and allows to obtain analogous formula for hypergeometric function. A new generating function for Jacobi polinomials with one of the parameters equal to zero is obtained.