Some decomposition formulas associated with the Lauricella function FA(r) and other multiple hypergeometric functions

By making use of some rather elementary techniques based upon certain inverse pairs of symbolic operators, the authors investigate several decomposition formulas associated with Lauricella’s hypergeometric function FA(r) in rr variables (r=2,3,4,…)(r=2,3,4,…) and also with other multiple hypergeometric functions. Alternative derivations of some of these decomposition formulas by means of (for example) integral representations are also indicated.