We calculate the genuine long-range multiparticle rapidity correlation functions, Cn(y1,",yn) for n=2,3,4,5,6, originating from fluctuations of the fireball longitudinal shape. In these correlation functions any contribution from the short-range two-particle correlations, and in general up to particle (n-1) in Cn, is suppressed. The information about the fluctuating fireball shape in rapidity is encoded in the cumulants of coefficients of the orthogonal polynomial expansion of particle distributions in rapidity.